41 * A <a href="package-summary.html#nominal">nominal descriptor</a> for a
42 * {@link Class} constant.
43 *
44 * <p>For common system types, including all the primitive types, there are
45 * predefined {@linkplain ClassDesc} constants in {@link ConstantDescs}.
46 * (The {@code java.lang.constant} APIs consider {@code void} to be a primitive type.)
47 * To create a {@linkplain ClassDesc} for a class or interface type, use {@link #of} or
48 * {@link #ofDescriptor(String)}; to create a {@linkplain ClassDesc} for an array
49 * type, use {@link #ofDescriptor(String)}, or first obtain a
50 * {@linkplain ClassDesc} for the component type and then call the {@link #arrayType()}
51 * or {@link #arrayType(int)} methods.
52 *
53 * @see ConstantDescs
54 *
55 * @since 12
56 */
57 public sealed interface ClassDesc
58 extends ConstantDesc,
59 TypeDescriptor.OfField<ClassDesc>
60 permits PrimitiveClassDescImpl,
61 ReferenceClassDescImpl {
62
63 /**
64 * Returns a {@linkplain ClassDesc} for a class or interface type,
65 * given the name of the class or interface, such as {@code "java.lang.String"}.
66 * (To create a descriptor for an array type, either use {@link #ofDescriptor(String)}
67 * or {@link #arrayType()}; to create a descriptor for a primitive type, use
68 * {@link #ofDescriptor(String)} or use the predefined constants in
69 * {@link ConstantDescs}).
70 *
71 * @param name the fully qualified (dot-separated) binary class name
72 * @return a {@linkplain ClassDesc} describing the desired class
73 * @throws NullPointerException if the argument is {@code null}
74 * @throws IllegalArgumentException if the name string is not in the
75 * correct format
76 * @see ClassDesc#ofDescriptor(String)
77 * @see ClassDesc#ofInternalName(String)
78 */
79 static ClassDesc of(String name) {
80 ConstantUtils.validateBinaryClassName(requireNonNull(name));
81 return ClassDesc.ofDescriptor("L" + binaryToInternal(name) + ";");
154 * correct format
155 * @jvms 4.3.2 Field Descriptors
156 * @jvms 4.4.1 The CONSTANT_Class_info Structure
157 * @see ClassDesc#of(String)
158 * @see ClassDesc#ofInternalName(String)
159 */
160 static ClassDesc ofDescriptor(String descriptor) {
161 requireNonNull(descriptor);
162 if (descriptor.isEmpty()) {
163 throw new IllegalArgumentException(
164 "not a valid reference type descriptor: " + descriptor);
165 }
166 int depth = ConstantUtils.arrayDepth(descriptor);
167 if (depth > ConstantUtils.MAX_ARRAY_TYPE_DESC_DIMENSIONS) {
168 throw new IllegalArgumentException(
169 "Cannot create an array type descriptor with more than " +
170 ConstantUtils.MAX_ARRAY_TYPE_DESC_DIMENSIONS + " dimensions");
171 }
172 return (descriptor.length() == 1)
173 ? new PrimitiveClassDescImpl(descriptor)
174 : new ReferenceClassDescImpl(descriptor);
175 }
176
177 /**
178 * Returns a {@linkplain ClassDesc} for an array type whose component type
179 * is described by this {@linkplain ClassDesc}.
180 *
181 * @return a {@linkplain ClassDesc} describing the array type
182 * @throws IllegalStateException if the resulting {@linkplain
183 * ClassDesc} would have an array rank of greater than 255
184 * @jvms 4.4.1 The CONSTANT_Class_info Structure
185 */
186 default ClassDesc arrayType() {
187 int depth = ConstantUtils.arrayDepth(descriptorString());
188 if (depth >= ConstantUtils.MAX_ARRAY_TYPE_DESC_DIMENSIONS) {
189 throw new IllegalStateException(
190 "Cannot create an array type descriptor with more than " +
191 ConstantUtils.MAX_ARRAY_TYPE_DESC_DIMENSIONS + " dimensions");
192 }
193 return arrayType(1);
194 }
280 */
281 default boolean isArray() {
282 return descriptorString().startsWith("[");
283 }
284
285 /**
286 * Returns whether this {@linkplain ClassDesc} describes a primitive type.
287 *
288 * @return whether this {@linkplain ClassDesc} describes a primitive type
289 */
290 default boolean isPrimitive() {
291 return descriptorString().length() == 1;
292 }
293
294 /**
295 * Returns whether this {@linkplain ClassDesc} describes a class or interface type.
296 *
297 * @return whether this {@linkplain ClassDesc} describes a class or interface type
298 */
299 default boolean isClassOrInterface() {
300 return descriptorString().startsWith("L");
301 }
302
303 /**
304 * Returns the component type of this {@linkplain ClassDesc}, if it describes
305 * an array type, or {@code null} otherwise.
306 *
307 * @return a {@linkplain ClassDesc} describing the component type, or {@code null}
308 * if this descriptor does not describe an array type
309 */
310 default ClassDesc componentType() {
311 return isArray() ? ClassDesc.ofDescriptor(descriptorString().substring(1)) : null;
312 }
313
314 /**
315 * Returns the package name of this {@linkplain ClassDesc}, if it describes
316 * a class or interface type.
317 *
318 * @return the package name, or the empty string if the class is in the
319 * default package, or this {@linkplain ClassDesc} does not describe a class or interface type
320 */
|
41 * A <a href="package-summary.html#nominal">nominal descriptor</a> for a
42 * {@link Class} constant.
43 *
44 * <p>For common system types, including all the primitive types, there are
45 * predefined {@linkplain ClassDesc} constants in {@link ConstantDescs}.
46 * (The {@code java.lang.constant} APIs consider {@code void} to be a primitive type.)
47 * To create a {@linkplain ClassDesc} for a class or interface type, use {@link #of} or
48 * {@link #ofDescriptor(String)}; to create a {@linkplain ClassDesc} for an array
49 * type, use {@link #ofDescriptor(String)}, or first obtain a
50 * {@linkplain ClassDesc} for the component type and then call the {@link #arrayType()}
51 * or {@link #arrayType(int)} methods.
52 *
53 * @see ConstantDescs
54 *
55 * @since 12
56 */
57 public sealed interface ClassDesc
58 extends ConstantDesc,
59 TypeDescriptor.OfField<ClassDesc>
60 permits PrimitiveClassDescImpl,
61 ClassDescImpl {
62
63 /**
64 * Returns a {@linkplain ClassDesc} for a class or interface type,
65 * given the name of the class or interface, such as {@code "java.lang.String"}.
66 * (To create a descriptor for an array type, either use {@link #ofDescriptor(String)}
67 * or {@link #arrayType()}; to create a descriptor for a primitive type, use
68 * {@link #ofDescriptor(String)} or use the predefined constants in
69 * {@link ConstantDescs}).
70 *
71 * @param name the fully qualified (dot-separated) binary class name
72 * @return a {@linkplain ClassDesc} describing the desired class
73 * @throws NullPointerException if the argument is {@code null}
74 * @throws IllegalArgumentException if the name string is not in the
75 * correct format
76 * @see ClassDesc#ofDescriptor(String)
77 * @see ClassDesc#ofInternalName(String)
78 */
79 static ClassDesc of(String name) {
80 ConstantUtils.validateBinaryClassName(requireNonNull(name));
81 return ClassDesc.ofDescriptor("L" + binaryToInternal(name) + ";");
154 * correct format
155 * @jvms 4.3.2 Field Descriptors
156 * @jvms 4.4.1 The CONSTANT_Class_info Structure
157 * @see ClassDesc#of(String)
158 * @see ClassDesc#ofInternalName(String)
159 */
160 static ClassDesc ofDescriptor(String descriptor) {
161 requireNonNull(descriptor);
162 if (descriptor.isEmpty()) {
163 throw new IllegalArgumentException(
164 "not a valid reference type descriptor: " + descriptor);
165 }
166 int depth = ConstantUtils.arrayDepth(descriptor);
167 if (depth > ConstantUtils.MAX_ARRAY_TYPE_DESC_DIMENSIONS) {
168 throw new IllegalArgumentException(
169 "Cannot create an array type descriptor with more than " +
170 ConstantUtils.MAX_ARRAY_TYPE_DESC_DIMENSIONS + " dimensions");
171 }
172 return (descriptor.length() == 1)
173 ? new PrimitiveClassDescImpl(descriptor)
174 : new ClassDescImpl(descriptor);
175 }
176
177 /**
178 * Returns a {@linkplain ClassDesc} for an array type whose component type
179 * is described by this {@linkplain ClassDesc}.
180 *
181 * @return a {@linkplain ClassDesc} describing the array type
182 * @throws IllegalStateException if the resulting {@linkplain
183 * ClassDesc} would have an array rank of greater than 255
184 * @jvms 4.4.1 The CONSTANT_Class_info Structure
185 */
186 default ClassDesc arrayType() {
187 int depth = ConstantUtils.arrayDepth(descriptorString());
188 if (depth >= ConstantUtils.MAX_ARRAY_TYPE_DESC_DIMENSIONS) {
189 throw new IllegalStateException(
190 "Cannot create an array type descriptor with more than " +
191 ConstantUtils.MAX_ARRAY_TYPE_DESC_DIMENSIONS + " dimensions");
192 }
193 return arrayType(1);
194 }
280 */
281 default boolean isArray() {
282 return descriptorString().startsWith("[");
283 }
284
285 /**
286 * Returns whether this {@linkplain ClassDesc} describes a primitive type.
287 *
288 * @return whether this {@linkplain ClassDesc} describes a primitive type
289 */
290 default boolean isPrimitive() {
291 return descriptorString().length() == 1;
292 }
293
294 /**
295 * Returns whether this {@linkplain ClassDesc} describes a class or interface type.
296 *
297 * @return whether this {@linkplain ClassDesc} describes a class or interface type
298 */
299 default boolean isClassOrInterface() {
300 return descriptorString().startsWith("L") || descriptorString().startsWith("Q");
301 }
302
303 /**
304 * Returns the component type of this {@linkplain ClassDesc}, if it describes
305 * an array type, or {@code null} otherwise.
306 *
307 * @return a {@linkplain ClassDesc} describing the component type, or {@code null}
308 * if this descriptor does not describe an array type
309 */
310 default ClassDesc componentType() {
311 return isArray() ? ClassDesc.ofDescriptor(descriptorString().substring(1)) : null;
312 }
313
314 /**
315 * Returns the package name of this {@linkplain ClassDesc}, if it describes
316 * a class or interface type.
317 *
318 * @return the package name, or the empty string if the class is in the
319 * default package, or this {@linkplain ClassDesc} does not describe a class or interface type
320 */
|