RELEASE NOTES FOR: 20 ==================================================================================================== Notes generated: Sun Sep 03 07:56:15 CEST 2023 Hint: Prefix bug IDs with https://bugs.openjdk.org/browse/ to reach the relevant JIRA entry. JAVA ENHANCEMENT PROPOSALS (JEP): JEP 429: Scoped Values (Incubator) Introduce _scoped values_, which enable the sharing of immutable data within and across threads. They are preferred to thread-local variables, especially when using large numbers of virtual threads. This is an [incubating API](https://openjdk.org/jeps/11). JEP 432: Record Patterns (Second Preview) Enhance the Java programming language with _record patterns_ to deconstruct record values. Record patterns and type patterns can be nested to enable a powerful, declarative, and composable form of data navigation and processing. This is a [preview language feature](https://openjdk.org/jeps/12). JEP 433: Pattern Matching for switch (Fourth Preview) Enhance the Java programming language with pattern matching for `switch` expressions and statements. Extending pattern matching to `switch` allows an expression to be tested against a number of patterns, each with a specific action, so that complex data-oriented queries can be expressed concisely and safely. This is a [preview language feature](https://openjdk.org/jeps/12). JEP 434: Foreign Function & Memory API (Second Preview) Introduce an API by which Java programs can interoperate with code and data outside of the Java runtime. By efficiently invoking foreign functions (i.e., code outside the JVM), and by safely accessing foreign memory (i.e., memory not managed by the JVM), the API enables Java programs to call native libraries and process native data without the brittleness and danger of JNI. This is a [preview API](https://openjdk.org/jeps/12). JEP 436: Virtual Threads (Second Preview) Introduce *virtual threads* to the Java Platform. Virtual threads are lightweight threads that dramatically reduce the effort of writing, maintaining, and observing high-throughput concurrent applications. This is a [preview API](https://openjdk.org/jeps/12). JEP 437: Structured Concurrency (Second Incubator) Simplify multithreaded programming by introducing an API for *structured concurrency*. Structured concurrency treats multiple tasks running in different threads as a single unit of work, thereby streamlining error handling and cancellation, improving reliability, and enhancing observability. This is an [incubating API](https://openjdk.org/jeps/11). JEP 438: Vector API (Fifth Incubator) Introduce an API to express vector computations that reliably compile at runtime to optimal vector instructions on supported CPU architectures, thus achieving performance superior to equivalent scalar computations. RELEASE NOTES: tools/javac: JDK-8244681: Javac Warns about Type Casts in Compound Assignments with Possible Lossy Conversions New lint option `lossy-conversions` has been added to `javac` to warn about type casts in compound assignments with possible lossy conversions. If the type of the right-hand operand of a compound assignment is not assignment compatible with the type of the variable, a cast is implied and possible lossy conversion may occur. The new warnings can be suppressed using `@SuppressWarnings("lossy-conversions")`. JDK-8173605: Remove Support for javac -source/-target/--release 7 Consistent with the policy outlined in [JEP 182: Policy for Retiring javac -source and -target Options](https://openjdk.java.net/jeps/182), support for the 7/1.7 argument value for javac's `-source`, `-target`, and `--release` flags has been removed. JDK-8297118: An Exhaustive Switch over an Enum Class Should Throw `MatchException` Rather Than `IncompatibleClassChangeError` If No Switch Label Applies at Runtime In this release, when preview features are enabled with `--enable-preview`, a `switch` expression over an enum type will throw a `MatchException` rather than an `IncompatibleClassChangeError` should the selector expression yield an unexpected enum constant value. This can only happen if the enum class has been changed by adding a new enum constant _after_ compilation of the `switch`. This change is required to unify the treatment of erroneous exhaustive switches introduced by enhancing `switch` with pattern labels. core-libs/java.net: JDK-8294241: java.net.URL Constructors Are Deprecated The `java.net.URL` constructors are deprecated in this release. Developers are encouraged to use `java.net.URI` to parse or construct a URL. In cases where an instance of `java.net.URL` is needed to open a connection, `java.net.URI` can be used to construct or parse the URL string, possibly calling `URI::parseServerAuthority()` to validate that the authority component can be parsed as a server-based authority, and then calling `URI::toURL()` to create the `URL` instance. A new method, `URL::of(URI, URLStreamHandler)` is provided for the advanced usages where there is a need to construct a `URL` with a given custom stream handler. See the `java.net.URL` API documentation [1] for more details [2]. [1] https://download.java.net/java/early_access/jdk20/docs/api/java.base/java/net/URL.html#constructor-summary [2] https://download.java.net/java/early_access/jdk20/docs/api/java.base/java/net/URL.html#constructor-deprecation JDK-8288717: Idle Connection Timeouts for HTTP/2 Idle Connection Timeouts for HTTP/2 are added in this release. The `jdk.httpclient.keepalivetimeout` property can now be used to configure a system-wide value, in seconds, used to close idle connections for both HTTP/1.1 and HTTP/2 when using the HttpClient. In addition, developer's can also use the `jdk.httpclient.keepalivetimeout.h2` to specify a timeout value exclusively for use with the HTTP/2 protocol, regardless of whether or not the jdk.httpclient.keepalivetimeout` is specified at runtime. See the java.net.http module and [Networking Properties](https://docs.oracle.com/en/java/javase/20/docs/api/java.base/java/net/doc-files/net-properties.html) in the JDK 20 API documentation for a list of current networking properties. JDK-8297030: HttpClient Default Keep Alive Time is 30 Seconds In this release, the default idle connection timeout value for the HTTP/1.1 and HTTP/2 connections created by the `java.net.http.HttpClient` has been reduced from 1200 seconds to 30 seconds. JDK-8293590: URL Constructors Called with Malformed Input May Throw MalformedURLException for Cases where It Was Not Thrown Previously The parsing of input provided to the `java.net.URL` constructors has changed in this release to be more strict. If the URL constructors are called with malformed input, then `MalformedURLException` may be thrown for cases where it wasn’t thrown previously. In previous releases, some of the parsing and validation performed by the JDK built-in `URLStreamHander` implementations was delayed until `URL::openConnection` or `URLConnection::connect` was called. Some of these parsing and validation actions are now performed early, within URL constructors. An exception caused by a malformed URL that would have been delayed until the connection was opened or connected might now cause a `MalformedURLException` to be thrown at URL construction time. This change only affects URL instances that delegate to JDK built-in stream handler implementations. Applications relying on custom, third party `URLStreamHandler` implementations should remain unaffected. A new JDK specific system property `-Djdk.net.url.delayParsing` or `-Djdk.net.url.delayParsing=true` can be specified on the command line to revert to the previous behavior. By default, the property is not set, and the new behavior is in place. This new property is provided for backward compatibility and may be removed in a future release. JDK-8294047: HTTP Response Input Streams Will Throw an IOException on Interrupt HTTP Response Input Streams are `InputStream` instances returned by the `ResponseSubscribers::ofInputStream` method. In this release, the default implementation of their `read` method was changed to throw an `IOException` if the thread performing this operation is interrupted, instead of ignoring the interruption. If the thread invoking the `read` operation is interrupted while blocking on `read`: * The request will be cancelled and the `InputStream` will be closed * The thread interrupt status will be set to true * An IOException will be thrown hotspot/jvmti: JDK-8296472: appendToClassPathForInstrumentation Must Be Used in a Thread-Safe Manner When running an application with a Java agent (e.g. `-javaagent:myagent.jar`) and a custom system class loader (e.g. `-Djava.system.class.loader=MyClassLoader`), and the Java agent invokes the `Instrumentation.appendToSystemClassLoaderSearch` API to append to the class loader search, then the custom system class loader `appendToClassPathForInstrumentation` method will be invoked to add the JAR file to the custom system class loader's search path. The JVM no longer synchronizes on the custom class loader while calling `appendToClassPathForInstrumentation`. The `appendToClassPathForInstrumentation` method in the custom class loader must add to the class search path in a thread-safe manner. JDK-8218885: can_pop_frame and can_force_early_return Capabilities are Disabled if JVMCI Compiler is Used The JVMTI `can_pop_frame` and `can_force_early_return` capabilities are disabled if a JVMCI compiler (like Graal) is used. As a result the corresponding functionality (`PopFrame` and `ForceEarlyReturnXXX` functions) is not available to JVMTI agents. This issue is tracked by [JDK-8218885](https://bugs.openjdk.java.net/browse/JDK-8218885). JDK-8288387: GetLocalXXX/SetLocalXXX Specification Should Require Suspending Target Thread The JVM TI specification of the GetLocalXXX/SetLocalXXX functions has been changed to require the target thread to be either suspended or the current thread. The error code JVMTI_ERROR_THREAD_NOT_SUSPENDED will be returned if this requirement is not satisfied. The JVM TI agents which use the GetLocalXXX/SetLocalXXX API's need to be updated to suspend the target thread if it is not the current thread. The full list of impacted JVM TI functions is: - GetLocalObject, GetLocalInt, GetLocalLong, GetLocalFloat, GetLocalDouble, GetLocalInstance, - SetLocalObject, SetLocalInt, SetLocalLong, SetLocalFloat, SetLocalDouble security-libs/javax.security: JDK-8297276: Remove Thread Text from Subject.current The specification of `Subject.current` has been changed in this release to drop the expectation that the `Subject` is inherited when creating a thread. At this time, the `Subject` is stored in the `AccessControlContext` and is inherited when creating platform threads. Virtual threads do not capture the caller context at thread creation time and the `AccessControlContext` is not inherited. Inheritance will be re-examined in a future release in advance of removing support for the `SecurityManager` and the inherited `AccessControlContext`. core-libs/java.util:i18n: JDK-8284840: Support for CLDR Version 42 Locale data based on Unicode Consortium's CLDR has been upgraded to version 42. For the detailed locale data changes, please refer to the [Unicode Consortium's CLDR release notes](https://cldr.unicode.org/index/downloads/cldr-42). Some of the notable changes in the upstream that may affect formatting are: - [NBSP/NNBSP prefixed to AM/PM in time format, instead of a normal space](https://unicode-org.atlassian.net/browse/CLDR-14032) - [" at " is no longer used for standard date/time format](https://unicode-org.atlassian.net/browse/CLDR-14831) - [Fix first day of week info for China (CN)](https://unicode-org.atlassian.net/browse/CLDR-11510) - [Japanese: Support numbers up to 9999京](https://unicode-org.atlassian.net/browse/CLDR-15966) core-libs/java.lang: JDK-8289551: java.lang.Float.floatToFloat16 and java.lang.Float.float16ToFloat May Return Different NaN Results when Optimized by the JIT Compiler JDK 20 introduces two new methods which can be used to convert to and from the IEEE 754 binary16 format: `java.lang.Float.floatToFloat16` and `java.lang.Float.float16ToFloat`. The new methods may return different NaN results when optimized by the JIT compiler. To disable the JIT compiler optimization of these methods, the following command line options can be used: `-XX:+UnlockDiagnosticVMOptions -XX:DisableIntrinsic=_floatToFloat16,_float16ToFloat` JDK-8249627: Thread.suspend/resume Changed to Throw UnsupportedOperationException The ability to suspend or resume a thread with the `Thread.suspend()` and `Thread.resume()` methods has been removed in this release. The methods have been changed to throw `UnsupportedOperationException`. These methods were inherently deadlock prone and have been deprecated since JDK 1.2 (1998). The corresponding methods in `ThreadGroup`, to suspend or resume a group of threads, were changed to throw `UnsupportedOperationException` in Java 19. JDK-8289610: java.lang.ThreadGroup Is degraded Legacy `java.lang.ThreadGroup` has been degraded in this release. It is no longer possible to explicitly destroy a thread group. In its place, `ThreadGroup` is changed to no longer keep a strong reference to subgroups. A thread group is thus eligible to be GC'ed when there are no live threads in the group and nothing else is keeping the thread group alive. The behavior of several methods, deprecated for removal in prior releases, are changed as follows: - The `destroy` method does nothing. - The `isDestroyed` method returns false. - The `setDaemon` and `isDaemon` methods set/get a daemon status that is not used for anything. - The `suspend`, `resume`, and `stop` methods throw `UnsupportedOperationException`. For further details, see the [JEP 425, section java.lang.ThreadGroup](https://openjdk.java.net/jeps/425#java-lang-ThreadGroup). JDK-8289610: Thread.Stop Changed to Throw UnsupportedOperationException The ability to "stop" a thread with the `Thread.stop()` method has been removed in this release. The method has been changed to throw `UnsupportedOperationException`. Stopping a thread by causing it to throw `java.lang.ThreadDeath` was inherently unsafe. The `stop` method has been deprecated since JDK 1.2 (1998). The corresponding method in `ThreadGroup`, to "stop" a group of threads, was changed to throw `UnsupportedOperationException` in Java 19. As part of this change, `java.lang.ThreadDeath` has been deprecated for removal. JDK-8284842: Support Unicode 15.0 This release upgrades the Unicode version to 15.0, which includes updated versions of the Unicode Character Database, Unicode Standard Annexes #9, #15, and #29: The `java.lang.Character` class supports Unicode Character Database, which adds 4,489 characters, for a total of 149,186 characters. These additions include 2 new scripts, for a total of 161 scripts, as well as 20 new emoji characters, and 4,193 CJK (Chinese, Japanese, and Korean) ideographs. The `java.text.Bidi` and `java.text.Normalizer` classes support Unicode Standard Annexes, #9 and #15, respectively. The `java.util.regex` package supports Extended Grapheme Clusters based on the Unicode Standard Annex #29. For more detail about Unicode 15.0, refer to the [Unicode Consortium’s release note](https://unicode.org/versions/Unicode15.0.0/). core-svc/javax.management: JDK-8297794: Deprecate JMX Management Applets for Removal The Java Management Extension (JMX) Management Applet (m-let) feature is deprecated for removal in a future release as it is irrelevant to modern applications - the deprecated public classes in `javax.management.loading` are: `MLet, MLetContent, PrivateMLet, MLetMBean`. This will have no impact on the JMX agent used for local and remote monitoring, the built-in instrumentation of the Java virtual machine, or tooling that uses JMX. hotspot/runtime: JDK-8290482: The JNI Specification Omits an Update to the JNI Version This bug updated the JNI Specification in relation to the `DestroyJavaVM` function. As part of that work, the JNI Specification version number was incremented. That change to the JNI Specification version should also have been reflected in the `GetVersion` function but was not. The `GetVersion` function for Java SE 20 and later has been updated to read `JNI_VERSION_20`. This new version has also been documented in `jni.h` as: ``` #define JNI_VERSION_20 0x00140000 ``` JDK-8295673: Deprecate and Disable Legacy Parallel Class Loading Workaround for Non-Parallel-Capable Class Loaders Some user-defined, older class loaders would workaround a deadlock issue by releasing the class loader lock during the loading process. To prevent these loaders from encountering a “java.lang.LinkageError: attempted duplicate class definition” while loading the same class by parallel threads, the HotSpot Virtual Machine introduced a workaround in JDK 6 that serialized the load attempts, causing the subsequent attempts to wait for the first to complete. The need for class loaders to work this way was removed in JDK 7 when parallel-capable class loaders were introduced, but the workaround remained in the VM. That workaround is finally being removed and as a first step has been deprecated and disabled by default. If you start seeing "java.lang.LinkageError: attempted duplicate class definition", then you may have an affected legacy class loader. The flag `-XX:+EnableWaitForParallelLoad` can be used to temporarily restore the old behavior in this release of the JDK, but the legacy class loader will need to be updated for future releases. See the CSR request (JDK-8295848) for more background and details. core-libs/java.util:collections: JDK-8178355: IdentityHashMap's Remove and Replace Methods Use Object Identity The `remove(key, value)` and `replace(key, oldValue, newValue)` implementations of `IdentityHashMap` have been corrected. In previous releases, the value arguments were compared with values in the map using `equals`. However, `IdentityHashMap` specifies that all such comparisons should be made using object identity (`==`). These methods' implementations now conform to the specification. security-libs/java.security: JDK-8292177: New JFR Event: jdk.InitialSecurityProperty A new Java Flight Recorder (JFR) event has been added to record details of initial security properties when loaded via the `java.security.Security` class. The new event name is `jdk.InitialSecurityProperty` and contains the following fields: | Field name | Field Description | | ------------------------ | --------------------------- | |key | Security Property Key | |value | Corresponding Security Property Value | This new JFR event is enabled by default. The `java.security.debug=properties` system property will also now print initial security properties to the standard error stream. With this new event and the already available `jdk.SecurityPropertyModification` event (when enabled since it is not enabled by default), a JFR recording can now monitor the initial settings of all security properties and any subsequent changes. JDK-8296226: Added Constructors (String, Throwable) and (Throwable) to InvalidParameterException Constructors `InvalidParameterException(String, Throwable)` and `InvalidParameterException(Throwable)` have been added to the `java.security.InvalidParameterException` class to support easy construction of `InvalidParameterException` objects with a cause. JDK-8155246: Throw Error If Default java.security File Fails to Load A behavioral change has been made when the default `conf/security/java.security` security configuration file fails to load. In such a scenario, the JDK will now throw an `InternalError`. Such a scenario should never occur. The default security file should always be present. Prior to this change, a static security configuration was loaded. JDK-8254711: New JFR Event: `jdk.SecurityProviderService` A new Java Flight Recorder (JFR) event has been added to record details of `java.security.Provider.getService(String type, String algorithm)` calls. The new event name is `jdk.SecurityProviderService` and contains the following fields: | Field name | Field Description | | ------------------------ | --------------------------- | |type | Type of Service | |algorithm |Algorithm Name | |provider | Security Provider | This event is disabled by default and can be enabled via the JFR configuration files or via standard JFR options. JDK-8282730: New Implementation Note for LoginModule on Removing Null from a Principals or Credentials Set The `Set` implementation that holds principals and credentials in a JAAS `Subject` prohibits null elements and any attempt to add, query, or remove a null element will result in a `NullPointerException`. This is especially important when trying to remove principals or credentials from the subject at the logout phase but they are null because of a previous failed login. Various JDK `LoginModule` implementations have been fixed to avoid the exception. An Implementation Note has also been added to the `logout()` method of the `LoginModule` interface. Developers should verify, and if necessary update, any custom `LoginModule` implementations to be compliant with this implementation advice. core-libs/java.time: JDK-8292579: Update Timezone Data to 2022c This version includes changes from 2022b that merged multiple regions that have the same timestamp data post-1970 into a single time zone database. All time zone IDs remain the same but the merged time zones will point to a shared zone database. As a result, pre-1970 data may not be compatible with earlier JDK versions. The affected zones are ```Antarctica/Vostok, Asia/Brunei, Asia/Kuala_Lumpur, Atlantic/Reykjavik, Europe/Amsterdam, Europe/Copenhagen, Europe/Luxembourg, Europe/Monaco, Europe/Oslo, Europe/Stockholm, Indian/Christmas, Indian/Cocos, Indian/Kerguelen, Indian/Mahe, Indian/Reunion, Pacific/Chuuk, Pacific/Funafuti, Pacific/Majuro, Pacific/Pohnpei, Pacific/Wake, Pacific/Wallis, Arctic/Longyearbyen, Atlantic/Jan_Mayen, Iceland, Pacific/Ponape, Pacific/Truk, and Pacific/Yap```. For more details, refer to the announcement of [2022b](https://mm.icann.org/pipermail/tz-announce/2022-August/000071.html) core-libs/java.text: JDK-8291660: Grapheme Support in BreakIterator Character boundary analysis in `java.text.BreakIterator` now conforms to Extended Grapheme Clusters breaks defined in Unicode Consortium's Standard Annex #29. This change will introduce intentional behavioral changes because the old implementation simply breaks at the code point boundaries for the vast majority of characters. For example, this is a String that contains the US flag and a grapheme for a 4-member-family. ``` "🇺🇸👨‍👩‍👧‍👦" ``` This String will be broken into two graphemes with the new implementation: ``` "🇺🇸", "👨‍👩‍👧‍👦" ``` whereas the old implementation simply breaks at the code point boundaries: ``` "🇺", "🇸", "👨", "(zwj)", "👩", "(zwj)", "👧", "(zwj)"‍, "👦" ``` where (zwj) denotes ZERO WIDTH JOINER (U+200D). core-svc/debugger: JDK-8280798: com.sun.jdi.ObjectReference::setValue Specification Should Prohibit Any Final Field Modification The specification of the Java Debug Interface (JDI) method `ObjectReference.setValue` has changed in this release to require the given field be non-final. The method was previously specified to require static fields be non-final but was silent on final instance fields. The JDK’s implementation of JDI has never allowed final instance fields to be changed with this method so this change has no impact on debuggers or tools using the JDK’s JDI implementation. Maintainers of JDI implementations should take note of this change so they can align their implementation with the updated specification. core-libs/javax.naming: JDK-8290368: Introduce LDAP and RMI Protocol Specific Object Factory Filters to JNDI Implementation In this release, new system and security properties are introduced to allow more granular control over the set of JNDI object factories allowed to reconstruct Java objects from JNDI/LDAP and JNDI/RMI contexts: * The new `jdk.jndi.ldap.object.factoriesFilter` property specifies which object factory classes are allowed to instantiate Java objects from object references returned by JNDI/LDAP contexts. Its default value only allows object factories defined in the `java.naming` module. * The new `jdk.jndi.rmi.object.factoriesFilter` property specifies which object factory classes are allowed to instantiate Java objects from object references returned by JNDI/RMI contexts. Its default value only allows object factories defined in the `jdk.rmi` module. These new factory filter properties complement the `jdk.jndi.object.factoriesFilter` global factories filter property by determining if a specific object factory is permitted to instantiate objects for the LDAP or RMI protocols used in JNDI. An application depending on custom object factories to recreate Java objects from JNDI/LDAP or JNDI/RMI contexts will need to supply a security or system property with an updated value to allow such third-party object factories to reconstruct LDAP or RMI objects. If usage of a factory is denied, the lookup operation may result in a plain instance of `javax.naming.Reference` instance returned, which may lead to a `ClassCastException` being thrown in the application. For more information, see the [java.naming](https://download.java.net/java/early_access/jdk20/docs/api/java.naming/module-summary.html) and [jdk.naming.rmi](https://download.java.net/java/early_access/jdk20/docs/api/jdk.naming.rmi/module-summary.html) module-info documentation. JDK-8290367: Update Default Value and Extend the Scope of com.sun.jndi.ldap.object.trustSerialData System Property In this release, the JDK implementation of the LDAP provider no longer supports deserialization of Java objects by default: * The default value of the `com.sun.jndi.ldap.object.trustSerialData` system property has been updated to `false`. * The scope of the `com.sun.jndi.ldap.object.trustSerialData` system property has been extended to cover the reconstruction of RMI remote objects from the `javaRemoteLocation` LDAP attribute. The transparent deserialization of Java objects from an LDAP context will now require an explicit opt-in. Applications that rely on reconstruction of Java objects or RMI stubs from the LDAP attributes would need to set the `com.sun.jndi.ldap.object.trustSerialData` system property to `true`. core-libs/java.util.jar: JDK-8292327: InflaterInputStream.read Throws EOFException A change to `java.util.zip.InflaterInputStream` in this release means it is possible that reading uncompressed bytes with this API can fail with an unexpected `java.io.EOFException`. The issue arises when reading uncompressed bytes with a byte array that isn't large enough to fit all bytes that have been uncompressed. In that case, the additional uncompressed bytes are buffered by the implementation to be consumed by the next call to the `read` method. If the compressed stream is at end of stream then a subsequent `read` of the uncompressed data will fail incorrectly with `EOFException`. This issue will be fixed in a future update. It may be possible to workaround the issue in some cases by calling `read` with a larger bye array. JDK-8282648: Weaken the InflaterInputStream Specification in Order to Allow Faster Zip Implementations The specification of the `read` methods defined by `java.util.zip.InflaterInputStream`,`ZipInputStream`, and `GZIPInputStream` have changed to allow these methods deviate from `InputStream.read` for the case that a “short read” occurs. A “short read” is the case where the user provides a buffer with space for M bytes but only N bytes (where 0 < N < M) are read. The long standing specification for `InputStream.read` is that N bytes are stored in the buffer provided by the user and elements at offset off+N to off+M-1 are not changed. The deviation allows the `read` method to use the elements at off+N to off+M-1 as temporary storage. Code using these APIs can no longer depend on these elements being unaffected when reading uncompressed data into a byte array. hotspot/compiler: JDK-8289552: java.lang.Float.floatToFloat16 and java.lang.Float.float16ToFloat May Return Different NaN Results when Optimized by the JIT Compiler JDK 20 introduces two new methods which can be used to convert to and from the IEEE 754 binary16 format: `java.lang.Float.floatToFloat16` and `java.lang.Float.float16ToFloat`. The new methods may return different NaN results when optimized by the JIT compiler. To disable the JIT compiler optimization of these methods, the following command line options can be used: `-XX:+UnlockDiagnosticVMOptions -XX:DisableIntrinsic=_floatToFloat16,_float16ToFloat` JDK-8288047: Provide Poly1305 Intrinsic on x86_64 platforms with AVX512 instructions This feature delivers optimized intrinsics using AVX512 instructions on x86_64 platforms for the Poly1305 Message Authentication Code algorithm of the SunJCE provider. This optimization is enabled by default on supporting x86_64 platforms, but may be disabled by providing the `-XX:+UnlockDiagnosticVMOptions -XX:-UsePoly1305Intrinsics` command-line options. security-libs/javax.net.ssl: JDK-8281236: (D)TLS Key Exchange Named Groups New Java SE APIs, `javax.net.ssl.SSLParameters.getNamedGroups()` and `javax.net.ssl.SSLParameters.setNamedGroups()`, have been added to allow applications to customize the named groups of key exchange algorithms used in individual TLS or DTLS connections. Note that the underlying provider may define the default named groups for each TLS or DTLS connection. Applications may also use the existing `jdk.tls.namedGroups` system property to customize the provider-specific default named groups. If not `null`, the named groups passed to the `setNamedGroups()` method will override the default named groups for the specified TLS or DTLS connections. Note that a provider may not have been updated to support the new APIs and in that case may ignore the named groups that are set. The JDK `SunJSSE` provider supports this method. It is recommended that third party providers add support for these methods when they add support for JDK 19 or later releases. JDK-8256660: Disabled DTLS 1.0 DTLS 1.0 has been disabled by default, by adding "DTLSv1.0" to the `jdk.tls.disabledAlgorithms` security property in the `java.security` configuration file. DTLS 1.0 has weakened over time and lacks support for stronger cipher suites. Any attempts to use DTLSv1.0 will fail with an `SSLHandshakeException`. Users can, at their own risk, re-enable the version by removing "DTLSv1.0" from the `jdk.tls.disabledAlgorithms` security property. JDK-8279164: Disabled TLS_ECDH_* Cipher Suites The TLS_ECDH_* cipher suites have been disabled by default, by adding "ECDH" to the `jdk.tls.disabledAlgorithms` security property in the `java.security` configuration file. The TLS_ECDH_* cipher suites do not preserve forward-secrecy and are rarely used in practice. Note that some TLS_ECDH_* cipher suites were already disabled because they use algorithms that are disabled, such as 3DES and RC4. This action disables the rest. Any attempts to use cipher suites starting with "TLS_ECDH_" will fail with an `SSLHandshakeException`. Users can, at their own risk, re-enable these cipher suites by removing "ECDH" from the `jdk.tls.disabledAlgorithms` security property. security-libs/javax.crypto: JDK-8247645: Provide ChaCha20 Intrinsics on x86_64 and aarch64 Platforms This feature delivers optimized intrinsic implementations for the ChaCha20 cipher supplied by the SunJCE provider. These optimized routines are designed for x86_64 chipsets that support the AVX, AVX2 and/or AVX512 instruction sets, and aarch64 chips supporting the Advanced SIMD instruction set. These intrinsics are enabled by default on supporting platforms, but may be disabled by providing the `-XX:-UseChaCha20Intrinsics` command-line option to Java. Flags that control intrinsics require the option` -XX:+UnlockDiagnosticVMOptions`. core-libs/java.nio: JDK-6924219: FileChannel Positional Write Is Unspecified in APPEND Mode The specification of `java.nio.channels.FileChannel` is updated to clarify that the effect of attempting to write at a specific position using the `FileChannel::write(ByteBuffer,long)` method is system-dependent when the channel is open in append mode. That is, a `java.nio.file.StandardOpenOption.APPEND` is passed to `FileChannel::open` when the channel is opened. In particular, on some operating systems, bytes will be written at the given position, while on other operating systems the given position will be ignored and the bytes will be appended to the file. JDK-8289689: Do Not Normalize File Paths to Unicode Normalization Format D on macOS On macOS, file names are no longer normalized to Apple's variant of Unicode Normalization Format D. File names were normalized on HFS+ prior to macOS 10.13, but on APFS on macOS 10.13 and newer, this normalization is no longer effected. The previous behavior may be enabled by setting the system property "jdk.nio.path.useNormalizationFormD" to "true". tools/javadoc(tool): JDK-8289332: Auto-Generated IDs in JavaDoc Headings JavaDoc now generates `id` attributes for all HTML headings in documentation comments that may be used as link anchors. JDK-8200337: Generalize see and link Tags for User-Defined Anchors The `{@link}`, `{@linkplain}` and `@see` tags have been enhanced to allow linking to arbitrary anchors in the JavaDoc-generated documentation for an element. To distinguish these references from member references, a double hash mark (`##`) is used to separate the element name from the URI fragment. JDK-8287597: Improved Preview API Page The Preview API page in the documentation generated by JavaDoc now provides detailed information about the JEPs the preview features belong to. core-libs/java.math: JDK-8289260: Restore Behavior of java.math.BigDecimal.movePointLeft() and movePointRight() on a Zero Argument When these methods are invoked with a zero argument on a target with a negative _scale_, they return a result which is numerically the same as the target, but with a different _unscaled value_ and _scale_. In earlier releases, they returned a result with the same _unscaled value_ and _scale_, which was against the specification. The behavior is unchanged when the target has a non-negative _scale_ or when the argument is not zero. core-libs/java.io: JDK-8290313: Print Warning to Standard Error If Bad java.io.tmpdir Setting Is Detected A new warning is now printed to the standard error stream at startup if a custom `java.io.tmpdir` system property is defined but the directory doesn't exist. The warning printed is: "WARNING: java.io.tmpdir directory does not exist" hotspot/gc: JDK-8292654: G1 Remembered set memory footprint regression after JDK-8286115 JDK-8286115 changed ergonomic sizing of a component of the remembered sets in G1. This change causes increased native memory usage of the Hotspot VM for applications that create large remembered sets with the G1 collector. In an internal benchmark total GC component native memory usage rose by almost 10% (from 1.2GB to 1.3GB). This issue can be worked around by passing double the value of `G1RemSetArrayOfCardsEntries` as printed by running the application with `-XX:+PrintFlagsFinal -XX:+UnlockExperimentalVMOptions` to your application. E.g. pass `-XX:+UnlockExperimentalVMOptions -XX:G1RemSetArrayOfCardsEntries=128` if a previous run showed a value of `64` for `G1RemSetArrayOfCardsEntries` in the output of `-XX:+PrintFlagsFinal`. This issue has been addressed in JDK 19.0.1 or later. JDK-8297247: Add GarbageCollectorMXBean for Remark and Cleanup Pause Time in G1 A new `GarbageCollectorMXBean` named "G1 Concurrent GC" has been added to the G1 garbage collector. This `GarbageCollectorMXBean` reports the occurrence and durations of the Remark and Cleanup garbage collection pauses. Similar to the "CGC" field from ``jstat -gcutil``, a complete concurrent mark cycle will increase the bean's collection counter by 2, one for the Remark and one for the Cleanup pauses. These pauses now also update the "G1 Old Gen" `MemoryManagerMXBean` memory pool. JDK-8137022: Improved Control of G1 Concurrent Refinement Threads The control of G1 concurrent refinement threads has been completely replaced. The new controller typically allocates fewer threads. It tends to have fewer spikes in refinement thread activity. It also tends to delay refinement, allowing more filtering by the write barrier when there are multiple writes to the same or nearby locations, improving the efficiency of the barrier. There are a number of command line options used to provide parameter values for the old controller. These aren't relevant to the new controller, and no longer serve any useful purpose. They have all been made obsolete; specifying any of them on the command line will do nothing but print a warning message about the option being obsolete. These arguments are: `-XX:-G1UseAdaptiveConcRefinement`
`-XX:G1ConcRefinementGreenZone=`_buffer-count_
`-XX:G1ConcRefinementYellowZone=`_buffer-count_
`-XX:G1ConcRefinementRedZone=`_buffer-count_
`-XX:G1ConcRefinementThresholdStep=`_buffer-count_
`-XX:G1ConcRefinementServiceIntervalMillis=`_msec_ These options will be removed entirely in some future release. Use of any of these options after that time will terminate startup of the virtual machine. JDK-8293861: G1: Disable Preventive GCs by Default In JDK 17, G1 added "preventive" garbage collections (GCs). These are speculative garbage collections, with the goal of avoiding costly evacuation failures due to allocation bursts when the heap is almost full. However, these speculative collections have the consequence of additional garbage collection work, as object aging is based on number of GCs with additional GCs causing premature promotion into the old generation, which leads to more data in the old generation, and more garbage collection work to remove these objects. This has been compounded by the current prediction to trigger preventive garbage collections being very conservative; which means these garbage collections are often triggered unnecessarily. In the majority of cases this feature is a net loss, and as evacuation failures are now handled more quickly, there is no longer any reason for this feature and it has been disabled by default, it may be re-enabled by `-XX:+UnlockDiagnosticVMOptions -XX:+G1UsePreventiveGC`. tools/jlink: JDK-8293499: New 'jmod --compress' Command Line Option A new `--compress` command line option has been added to the `jmod` tool to specify the compression level while creating the JMOD archive. The accepted values are `zip-[0-9]`, where `zip-0` provides no compression, and `zip-9` provides the best compression. Default is `zip-6`. core-svc/java.lang.management: JDK-8283093: JMX Connections Use an ObjectInputFilter by Default The default JMX agent now sets an ObjectInputFilter on the RMI connection to restrict the types that the server will deserialize. This should not affect normal usage of the MBeans in the JDK. Applications which register their own MBeans in the Platform MBeanServer may need to extend the filter to support any additional types that their MBeans accept as parameters. The default filter already covers any type that OpenMBeans and MXBeans might use. The filter pattern is set in `JDK/conf/management/management.properties` using the property `com.sun.management.jmxremote.serial.filter.pattern`. If there are additional Java types that need to be passed, the default can be overridden by running with `-Dcom.sun.management.jmxremote.serial.filter.pattern=`. Serialization Filtering and the filter pattern format are described in detail in the Core Libraries guide. ALL FIXED ISSUES, BY COMPONENT AND PRIORITY: client-libs: (P3) JDK-8293672: Update freetype md file (P4) JDK-8286270: [java.desktop] Replace color search in XColors with a switch statement (P4) JDK-8292314: Cleanup legacy address handling (P4) JDK-8292309: Fix java/awt/PrintJob/ConstrainedPrintingTest/ConstrainedPrintingTest.java test (P4) JDK-8285306: Fix typos in java.desktop (P4) JDK-8290162: Reset recursion counter missed in fix of JDK-8224267 (P5) JDK-8284672: Collapse identical catch branches in java.desktop (P5) JDK-8292350: Use static methods for hashCode/toString primitives client-libs/2d: (P1) JDK-8297507: Update header after JDK-8297230 (P2) JDK-8292305: [BACKOUT] JDK-8289208 Test DrawRotatedStringUsingRotatedFont.java occasionally crashes on MacOS (P3) JDK-8295369: [Attempted] Update LCMS to 2.14 (P3) JDK-8292304: [REDO] JDK-8289208 Test DrawRotatedStringUsingRotatedFont.java occasionally crashes on MacOS (P3) JDK-8289697: buffer overflow in MTLVertexCache.m: MTLVertexCache_AddGlyphQuad (P3) JDK-8288948: Few J2DBench tests indicate lower primitive drawing performance with metal rendering pipeline (P3) JDK-8264999: GeneralPath.lineTo() to itself produces jagged lines (P3) JDK-8292214: Memory leak in getAllConfigs of awt_GraphicsEnv.c:386 (P3) JDK-8298217: Regressions 30-110% in SwingMark on MacOS, more so on aarch64 (P3) JDK-8291266: RenderPerfTest: missing content while rendering some primitives (P3) JDK-8022403: sun/java2d/DirectX/OnScreenRenderingResizeTest/OnScreenRenderingResizeTest.java fails (P3) JDK-8297153: sun/java2d/DirectX/OnScreenRenderingResizeTest/OnScreenRenderingResizeTest.java fails again (P3) JDK-8289208: Test DrawRotatedStringUsingRotatedFont.java occasionally crashes on MacOS (P3) JDK-8290334: Update FreeType to 2.12.1 (P3) JDK-8289853: Update HarfBuzz to 4.4.1 (P3) JDK-8297088: Update LCMS to 2.14 (P3) JDK-8297230: Update Marlin2D to 0.9.4.6 (P3) JDK-8297241: Update sun/java2d/DirectX/OnScreenRenderingResizeTest/OnScreenRenderingResizeTest.java (P3) JDK-8190907: Windows 10 default Korean Font Malgun Gothic available not used by GUI elements even though available without Korean Language Pack (P4) JDK-8297089: [BACKOUT] JDK-8297088 Update LCMS to 2.14 (P4) JDK-8191406: [hidpi] sun/java2d/SunGraphics2D/DrawImageBilinear.java test fails (P4) JDK-8288067: Avoid redundant HashMap.containsKey call in Type1Font.expandAbbreviation (P4) JDK-4677581: ColorModel.getComponentSize()-wrong conditions for ArrayIndexOutOfBoundsExceptio (P4) JDK-8297676: DataBuffer.TYPE_SHORT/TYPE_FLOAT/TYPE_DOUBLE are not placeholders (P4) JDK-8294488: Delete KCMS transforms wrappers (P4) JDK-8290973: In AffineTransform, equals(Object) is inconsistent with hashCode() (P4) JDK-8165943: LineBreakMeasurer does not measure correctly if TextAttribute.TRACKING is set. (P4) JDK-8298027: Remove SCCS id's from awt jtreg tests (P4) JDK-8296905: Replace the native LCMS#getProfileID() method with the accessor (P4) JDK-8295812: Skip the "half float" support in LittleCMS during the build (P4) JDK-6528710: sRGB-ColorSpace to sRGB-ColorSpace Conversion (P4) JDK-8290344: Start/stop displaysync affects performance in metal rendering pipeline (P4) JDK-8288633: The ICC_ColorSpace.fromCIEXYZ method uses the wrong rendering intent (P4) JDK-8297147: UnexpectedSourceImageSize test times out on slow machines when fastdebug is used (P4) JDK-8297681: Unnecessary color conversion during 4BYTE_ABGR_PRE to INT_ARGB_PRE blit (P4) JDK-8295430: Use cmsDoTransformLineStride instead of cmsDoTransform in the loop (P5) JDK-8293767: AWT test TestSinhalaChar.java has old SCCS markings (P5) JDK-8295003: Do not mention applets in the "java.awt.color" package (P5) JDK-8292026: Remove redundant allocations from DoubleByteEncoder (P5) JDK-8295767: Remove unused fields in sun.awt.geom.Edge (P5) JDK-8293159: Use try-with-resources in X11FontManager.registerFontDir client-libs/java.awt: (P1) JDK-8288332: Tier1 validate-source fails after 8279614 (P2) JDK-8295685: Update Libpng to 1.6.38 (P3) JDK-8294067: [macOS] javax/swing/JComboBox/6559152/bug6559152.java Cannot select an item from popup with the ENTER key. (P3) JDK-8294254: [macOS] javax/swing/plaf/aqua/CustomComboBoxFocusTest.java failure (P3) JDK-8164464: Consistent failure of java/awt/dnd/MissingEventsOnModalDialog/MissingEventsOnModalDialogTest.java (P3) JDK-8282526: Default icon is not painted properly (P3) JDK-8289616: Drop use of Thread.stop in AppContext (P3) JDK-8296957: One more cast in SAFE_SIZE_NEW_ARRAY2 (P3) JDK-8296496: Overzealous check in sizecalc.h prevents large memory allocation (P3) JDK-8294039: Remove "Classpath" exception from java/awt tests (P3) JDK-8279614: The left line of the TitledBorder is not painted on 150 scale factor (P4) JDK-8239801: [macos] java/awt/Focus/UnaccessibleChoice/AccessibleChoiceTest.java fails (P4) JDK-8157173: [macosx] java/awt/Robot/ModifierRobotKey/ModifierRobotKeyTest.java fails (P4) JDK-8288325: [windows] Actual and Preferred Size of AWT Non-resizable frame are different (P4) JDK-8265586: [windows] last button is not shown in AWT Frame with BorderLayout and MenuBar set. (P4) JDK-8294255: Add link to DEFAULT_WAIT_TIME in javadoc for SunToolKit.realsSync (P4) JDK-8292848: AWT_Mixing and TrayIcon tests fail on el8 with hard-coded isOel7 (P4) JDK-8297195: AWTAccessor and SwingAccessor should avoid double racy reads from non-volatile fields (P4) JDK-8252075: Documentation error in LayoutManager2 interface (P4) JDK-8291959: FileFontStrike#initNative does not properly initialize IG Table on Windows (P4) JDK-8196018: java/awt/Scrollbar/ScrollbarMouseWheelTest/ScrollbarMouseWheelTest.java fails (P4) JDK-8292866: Java_sun_awt_shell_Win32ShellFolder2_getLinkLocation check MultiByteToWideChar return value for failures (P4) JDK-8295554: Move the "sizecalc.h" to the correct location (P4) JDK-8276849: Refresh the window icon on graphics configuration changes (P4) JDK-8288444: Remove the workaround for frame.pack() in ModalDialogTest (P4) JDK-8148041: Test java/awt/Mouse/TitleBarDoubleClick/TitleBarDoubleClick fails on Ubuntu with mouseReleased event after double click on title bar (P4) JDK-8294426: Two fingers tap generates wrong mouse modifiers on M2 MacBooks (P4) JDK-8297523: Various GetPrimitiveArrayCritical miss result - NULL check (P5) JDK-8288993: Make AwtFramePackTest generic by removing @requires tag client-libs/java.beans: (P5) JDK-8293986: Incorrect double-checked locking in com.sun.beans.introspect.ClassInfo (P5) JDK-8293984: Unnecessary Vector usage in PropertyEditorSupport client-libs/javax.accessibility: (P4) JDK-8286313: [macos] Voice over reads the boolean value as null in the JTable (P4) JDK-8292328: AccessibleActionsTest.java test instruction for show popup on JLabel did not specify shift key (P4) JDK-8296222: SwingEventMonitor - installListeners(Component , int ) - CELLEDITOR - bug (P5) JDK-8292280: Unused field 'keyListener' in BasicRadioButtonUI client-libs/javax.imageio: (P3) JDK-8278086: [REDO] ImageIO.write() method will throw IndexOutOfBoundsException (P3) JDK-8270915: GIFImageReader disregards ignoreMetadata flag which causes memory exhaustion (P3) JDK-8272998: ImageIO.read() throws incorrect exception type (P4) JDK-8297480: GetPrimitiveArrayCritical in imageioJPEG misses result - NULL check (P4) JDK-8299227: host `exif.org` not found in link in doc comment (P5) JDK-8297750: Unnecessary Vector usage in IIORegistry client-libs/javax.sound: (P3) JDK-8282578: AIOOBE in javax.sound.sampled.Clip (P4) JDK-8282463: javax/sound/sampled/Clip/DataPusherThreadCheck.java fails client-libs/javax.swing: (P2) JDK-8299123: [BACKOUT] 4512626 Non-editable JTextArea provides no visual indication of keyboard focus (P2) JDK-8292062: misc javax/swing tests failing (P2) JDK-8301989: new javax.swing.text.DefaultCaret().setBlinkRate(N) results in NPE (P2) JDK-8298083: The "CheckBox/RadioButton[Enabled/Disabled].textForeground" stoped working (P2) JDK-8300269: The selected item in an editable JComboBox with titled border is not visible in Aqua LAF (P3) JDK-8170794: [macosx] Error when using setDesktopManager on a JDesktopPane on MacOS X with Look and Feel Aqua (P3) JDK-8064787: [macosx] In Nimbus LaF, Ctrl+Alt mnemonic doesn't work (P3) JDK-8299077: [REDO] JDK-4512626 Non-editable JTextArea provides no visual indication of keyboard focus (P3) JDK-8295006: Colored text is not shown on disabled checkbox and radio button with GTK LAF for bug4314194. (P3) JDK-8296878: Document Filter attached to JPasswordField and setText("") is not cleared instead inserted characters replaced with unicode null characters (P3) JDK-8012675: javax.swing.JEditorPane is unclear on the handling of unsupported HTML script tags (P3) JDK-8292948: JEditorPane ignores font-size styles in external linked css-file (P3) JDK-8288882: JFileChooser - empty (0 bytes) file is displayed as 1 KB (P3) JDK-8296198: JFileChooser throws InternalError java.lang.InternalError with Windows shortcuts (P3) JDK-8224267: JOptionPane message string with 5000+ newlines produces StackOverflowError (P3) JDK-8259687: JTabbedPane.setComponentAt doesn't hide previously visible tab component (P3) JDK-8267374: macOS: Option+Up/Down Arrow don't traverse to beginning/end of line in JTextArea (P3) JDK-8294046: Newly added test test/jdk/javax/swing/JTabbedPane/TestNPEStateChgListener.java fails in macos (P3) JDK-4512626: Non-editable JTextArea provides no visual indication of keyboard focus (P3) JDK-6529151: NullPointerException in swing.plaf.synth.SynthLookAndFeel$Handler (P3) JDK-6852577: Only for Nimbus LAF UIManager.get("PasswordField.echoChar") is null (P3) JDK-8294038: Remove "Classpath" exception from javax/swing tests (P3) JDK-8282958: Rendering Issues with Borders on Windows High-DPI systems (P3) JDK-8296660: Swing HTML table with omitted closing tags misparsed (P3) JDK-8075916: The regression-swing case failed as colored text is not shown on disabled checkbox and radio button with Nimbus LAF (P4) JDK-8290399: [macos] Aqua LAF does not fire an action event if combo box menu is displayed (P4) JDK-7132413: [macosx] closed/javax/swing/AbstractButton/5049549/bug5049549.java fails on MacOS (P4) JDK-7134652: [macosx] closed/javax/swing/SwingUtilities/4967768/bug4967768.java fails on MacOS (P4) JDK-8065097: [macosx] javax/swing/Popup/TaskbarPositionTest.java fails because Popup is one pixel off (P4) JDK-8054572: [macosx] JComboBox paints the border incorrectly (P4) JDK-7189422: [macosx] Submenu's arrow have a wrong position (P4) JDK-7124313: [macosx] Swing Popups should overlap taskbar (P4) JDK-7148092: [macosx] When Alt+down arrow key is pressed, the combobox popup does not appear. (P4) JDK-8292376: A few Swing methods use inheritDoc on exceptions which are not inherited (P4) JDK-8281966: Absolute path of symlink is null in JFileChooser (P4) JDK-8295738: Automate javax/swing/JFileChooser/FileSizeCheck.java (P4) JDK-8295298: Automate javax/swing/JFileChooser/FileViewNPETest.java (P4) JDK-8015739: Background of JInternalFrame is located out of JInternalFrame (P4) JDK-8078471: Backspace does not work in JFileChooser with GTK L&F (P4) JDK-6229853: BasicTextAreaUI:create incompletely documents the possible returned View types (P4) JDK-6972078: Can not select single directory with GTKLookAndFeel (P4) JDK-6788481: CellEditorListener.editingCanceled is never called (P4) JDK-6521141: DebugGraphics NPE @ setFont(); (P4) JDK-6463708: DefaultButtonModel.setMnemonic generates ChangeEvent for no change (P4) JDK-8291792: DefaultStyledDocument.setCharacterAttributes accepts negative length (P4) JDK-6201035: Document NPE for passing null insets to constructors and methods of several javax.swing.border.* classes (P4) JDK-8277775: Fixup bugids in RemoveDropTargetCrashTest.java - add 4357905 (P4) JDK-8287912: GTK L&F : Background of tree icons are red (P4) JDK-6777156: GTK L&F: JFileChooser can jump beyond root directory in combobox and selection textarea. (P4) JDK-8234315: GTK LAF does not gray out disabled JMenu (P4) JDK-7172359: HTML parser StackOverflowError on invalid HTML:
  • tag inside an