JDK14/Java14源码在线阅读
JDK14/Java14源码在线阅读 /
java.base /
share /
classes /
jdk /
internal /
org /
objectweb /
asm /
Type.java
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* This file is available under and governed by the GNU General Public
* License version 2 only, as published by the Free Software Foundation.
* However, the following notice accompanied the original version of this
* file:
*
* ASM: a very small and fast Java bytecode manipulation framework
* Copyright (c) 2000-2011 INRIA, France Telecom
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
package jdk.internal.org.objectweb.asm;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
/**
* A Java field or method type. This class can be used to make it easier to manipulate type and
* method descriptors.
*
* @author Eric Bruneton
* @author Chris Nokleberg
*/
public final class Type {
/** The sort of the {@code void} type. See {@link #getSort}. */
public static final int VOID = 0;
/** The sort of the {@code boolean} type. See {@link #getSort}. */
public static final int BOOLEAN = 1;
/** The sort of the {@code char} type. See {@link #getSort}. */
public static final int CHAR = 2;
/** The sort of the {@code byte} type. See {@link #getSort}. */
public static final int BYTE = 3;
/** The sort of the {@code short} type. See {@link #getSort}. */
public static final int SHORT = 4;
/** The sort of the {@code int} type. See {@link #getSort}. */
public static final int INT = 5;
/** The sort of the {@code float} type. See {@link #getSort}. */
public static final int FLOAT = 6;
/** The sort of the {@code long} type. See {@link #getSort}. */
public static final int LONG = 7;
/** The sort of the {@code double} type. See {@link #getSort}. */
public static final int DOUBLE = 8;
/** The sort of array reference types. See {@link #getSort}. */
public static final int ARRAY = 9;
/** The sort of object reference types. See {@link #getSort}. */
public static final int OBJECT = 10;
/** The sort of method types. See {@link #getSort}. */
public static final int METHOD = 11;
/** The (private) sort of object reference types represented with an internal name. */
private static final int INTERNAL = 12;
/** The descriptors of the primitive types. */
private static final String PRIMITIVE_DESCRIPTORS = "VZCBSIFJD";
/** The {@code void} type. */
public static final Type VOID_TYPE = new Type(VOID, PRIMITIVE_DESCRIPTORS, VOID, VOID + 1);
/** The {@code boolean} type. */
public static final Type BOOLEAN_TYPE =
new Type(BOOLEAN, PRIMITIVE_DESCRIPTORS, BOOLEAN, BOOLEAN + 1);
/** The {@code char} type. */
public static final Type CHAR_TYPE = new Type(CHAR, PRIMITIVE_DESCRIPTORS, CHAR, CHAR + 1);
/** The {@code byte} type. */
public static final Type BYTE_TYPE = new Type(BYTE, PRIMITIVE_DESCRIPTORS, BYTE, BYTE + 1);
/** The {@code short} type. */
public static final Type SHORT_TYPE = new Type(SHORT, PRIMITIVE_DESCRIPTORS, SHORT, SHORT + 1);
/** The {@code int} type. */
public static final Type INT_TYPE = new Type(INT, PRIMITIVE_DESCRIPTORS, INT, INT + 1);
/** The {@code float} type. */
public static final Type FLOAT_TYPE = new Type(FLOAT, PRIMITIVE_DESCRIPTORS, FLOAT, FLOAT + 1);
/** The {@code long} type. */
public static final Type LONG_TYPE = new Type(LONG, PRIMITIVE_DESCRIPTORS, LONG, LONG + 1);
/** The {@code double} type. */
public static final Type DOUBLE_TYPE =
new Type(DOUBLE, PRIMITIVE_DESCRIPTORS, DOUBLE, DOUBLE + 1);
// -----------------------------------------------------------------------------------------------
// Fields
// -----------------------------------------------------------------------------------------------
/**
* The sort of this type. Either {@link #VOID}, {@link #BOOLEAN}, {@link #CHAR}, {@link #BYTE},
* {@link #SHORT}, {@link #INT}, {@link #FLOAT}, {@link #LONG}, {@link #DOUBLE}, {@link #ARRAY},
* {@link #OBJECT}, {@link #METHOD} or {@link #INTERNAL}.
*/
private final int sort;
/**
* A buffer containing the value of this field or method type. This value is an internal name for
* {@link #OBJECT} and {@link #INTERNAL} types, and a field or method descriptor in the other
* cases.
*
* <p>For {@link #OBJECT} types, this field also contains the descriptor: the characters in
* [{@link #valueBegin},{@link #valueEnd}) contain the internal name, and those in [{@link
* #valueBegin} - 1, {@link #valueEnd} + 1) contain the descriptor.
*/
private final String valueBuffer;
/**
* The beginning index, inclusive, of the value of this Java field or method type in {@link
* #valueBuffer}. This value is an internal name for {@link #OBJECT} and {@link #INTERNAL} types,
* and a field or method descriptor in the other cases.
*/
private final int valueBegin;
/**
* The end index, exclusive, of the value of this Java field or method type in {@link
* #valueBuffer}. This value is an internal name for {@link #OBJECT} and {@link #INTERNAL} types,
* and a field or method descriptor in the other cases.
*/
private final int valueEnd;
/**
* Constructs a reference type.
*
* @param sort the sort of this type, see {@link #sort}.
* @param valueBuffer a buffer containing the value of this field or method type.
* @param valueBegin the beginning index, inclusive, of the value of this field or method type in
* valueBuffer.
* @param valueEnd the end index, exclusive, of the value of this field or method type in
* valueBuffer.
*/
private Type(final int sort, final String valueBuffer, final int valueBegin, final int valueEnd) {
this.sort = sort;
this.valueBuffer = valueBuffer;
this.valueBegin = valueBegin;
this.valueEnd = valueEnd;
}
// -----------------------------------------------------------------------------------------------
// Methods to get Type(s) from a descriptor, a reflected Method or Constructor, other types, etc.
// -----------------------------------------------------------------------------------------------
/**
* Returns the {@link Type} corresponding to the given type descriptor.
*
* @param typeDescriptor a field or method type descriptor.
* @return the {@link Type} corresponding to the given type descriptor.
*/
public static Type getType(final String typeDescriptor) {
return getTypeInternal(typeDescriptor, 0, typeDescriptor.length());
}
/**
* Returns the {@link Type} corresponding to the given class.
*
* @param clazz a class.
* @return the {@link Type} corresponding to the given class.
*/
public static Type getType(final Class<?> clazz) {
if (clazz.isPrimitive()) {
if (clazz == Integer.TYPE) {
return INT_TYPE;
} else if (clazz == Void.TYPE) {
return VOID_TYPE;
} else if (clazz == Boolean.TYPE) {
return BOOLEAN_TYPE;
} else if (clazz == Byte.TYPE) {
return BYTE_TYPE;
} else if (clazz == Character.TYPE) {
return CHAR_TYPE;
} else if (clazz == Short.TYPE) {
return SHORT_TYPE;
} else if (clazz == Double.TYPE) {
return DOUBLE_TYPE;
} else if (clazz == Float.TYPE) {
return FLOAT_TYPE;
} else if (clazz == Long.TYPE) {
return LONG_TYPE;
} else {
throw new AssertionError();
}
} else {
return getType(getDescriptor(clazz));
}
}
/**
* Returns the method {@link Type} corresponding to the given constructor.
*
* @param constructor a {@link Constructor} object.
* @return the method {@link Type} corresponding to the given constructor.
*/
public static Type getType(final Constructor<?> constructor) {
return getType(getConstructorDescriptor(constructor));
}
/**
* Returns the method {@link Type} corresponding to the given method.
*
* @param method a {@link Method} object.
* @return the method {@link Type} corresponding to the given method.
*/
public static Type getType(final Method method) {
return getType(getMethodDescriptor(method));
}
/**
* Returns the type of the elements of this array type. This method should only be used for an
* array type.
*
* @return Returns the type of the elements of this array type.
*/
public Type getElementType() {
final int numDimensions = getDimensions();
return getTypeInternal(valueBuffer, valueBegin + numDimensions, valueEnd);
}
/**
* Returns the {@link Type} corresponding to the given internal name.
*
* @param internalName an internal name.
* @return the {@link Type} corresponding to the given internal name.
*/
public static Type getObjectType(final String internalName) {
return new Type(
internalName.charAt(0) == '[' ? ARRAY : INTERNAL, internalName, 0, internalName.length());
}
/**
* Returns the {@link Type} corresponding to the given method descriptor. Equivalent to <code>
* Type.getType(methodDescriptor)</code>.
*
* @param methodDescriptor a method descriptor.
* @return the {@link Type} corresponding to the given method descriptor.
*/
public static Type getMethodType(final String methodDescriptor) {
return new Type(METHOD, methodDescriptor, 0, methodDescriptor.length());
}
/**
* Returns the method {@link Type} corresponding to the given argument and return types.
*
* @param returnType the return type of the method.
* @param argumentTypes the argument types of the method.
* @return the method {@link Type} corresponding to the given argument and return types.
*/
public static Type getMethodType(final Type returnType, final Type... argumentTypes) {
return getType(getMethodDescriptor(returnType, argumentTypes));
}
/**
* Returns the argument types of methods of this type. This method should only be used for method
* types.
*
* @return the argument types of methods of this type.
*/
public Type[] getArgumentTypes() {
return getArgumentTypes(getDescriptor());
}
/**
* Returns the {@link Type} values corresponding to the argument types of the given method
* descriptor.
*
* @param methodDescriptor a method descriptor.
* @return the {@link Type} values corresponding to the argument types of the given method
* descriptor.
*/
public static Type[] getArgumentTypes(final String methodDescriptor) {
// First step: compute the number of argument types in methodDescriptor.
int numArgumentTypes = 0;
// Skip the first character, which is always a '('.
int currentOffset = 1;
// Parse the argument types, one at a each loop iteration.
while (methodDescriptor.charAt(currentOffset) != ')') {
while (methodDescriptor.charAt(currentOffset) == '[') {
currentOffset++;
}
if (methodDescriptor.charAt(currentOffset++) == 'L') {
// Skip the argument descriptor content.
currentOffset = methodDescriptor.indexOf(';', currentOffset) + 1;
}
++numArgumentTypes;
}
// Second step: create a Type instance for each argument type.
Type[] argumentTypes = new Type[numArgumentTypes];
// Skip the first character, which is always a '('.
currentOffset = 1;
// Parse and create the argument types, one at each loop iteration.
int currentArgumentTypeIndex = 0;
while (methodDescriptor.charAt(currentOffset) != ')') {
final int currentArgumentTypeOffset = currentOffset;
while (methodDescriptor.charAt(currentOffset) == '[') {
currentOffset++;
}
if (methodDescriptor.charAt(currentOffset++) == 'L') {
// Skip the argument descriptor content.
currentOffset = methodDescriptor.indexOf(';', currentOffset) + 1;
}
argumentTypes[currentArgumentTypeIndex++] =
getTypeInternal(methodDescriptor, currentArgumentTypeOffset, currentOffset);
}
return argumentTypes;
}
/**
* Returns the {@link Type} values corresponding to the argument types of the given method.
*
* @param method a method.
* @return the {@link Type} values corresponding to the argument types of the given method.
*/
public static Type[] getArgumentTypes(final Method method) {
Class<?>[] classes = method.getParameterTypes();
Type[] types = new Type[classes.length];
for (int i = classes.length - 1; i >= 0; --i) {
types[i] = getType(classes[i]);
}
return types;
}
/**
* Returns the return type of methods of this type. This method should only be used for method
* types.
*
* @return the return type of methods of this type.
*/
public Type getReturnType() {
return getReturnType(getDescriptor());
}
/**
* Returns the {@link Type} corresponding to the return type of the given method descriptor.
*
* @param methodDescriptor a method descriptor.
* @return the {@link Type} corresponding to the return type of the given method descriptor.
*/
public static Type getReturnType(final String methodDescriptor) {
// Skip the first character, which is always a '('.
int currentOffset = 1;
// Skip the argument types, one at a each loop iteration.
while (methodDescriptor.charAt(currentOffset) != ')') {
while (methodDescriptor.charAt(currentOffset) == '[') {
currentOffset++;
}
if (methodDescriptor.charAt(currentOffset++) == 'L') {
// Skip the argument descriptor content.
currentOffset = methodDescriptor.indexOf(';', currentOffset) + 1;
}
}
return getTypeInternal(methodDescriptor, currentOffset + 1, methodDescriptor.length());
}
/**
* Returns the {@link Type} corresponding to the return type of the given method.
*
* @param method a method.
* @return the {@link Type} corresponding to the return type of the given method.
*/
public static Type getReturnType(final Method method) {
return getType(method.getReturnType());
}
/**
* Returns the {@link Type} corresponding to the given field or method descriptor.
*
* @param descriptorBuffer a buffer containing the field or method descriptor.
* @param descriptorBegin the beginning index, inclusive, of the field or method descriptor in
* descriptorBuffer.
* @param descriptorEnd the end index, exclusive, of the field or method descriptor in
* descriptorBuffer.
* @return the {@link Type} corresponding to the given type descriptor.
*/
private static Type getTypeInternal(
final String descriptorBuffer, final int descriptorBegin, final int descriptorEnd) {
switch (descriptorBuffer.charAt(descriptorBegin)) {
case 'V':
return VOID_TYPE;
case 'Z':
return BOOLEAN_TYPE;
case 'C':
return CHAR_TYPE;
case 'B':
return BYTE_TYPE;
case 'S':
return SHORT_TYPE;
case 'I':
return INT_TYPE;
case 'F':
return FLOAT_TYPE;
case 'J':
return LONG_TYPE;
case 'D':
return DOUBLE_TYPE;
case '[':
return new Type(ARRAY, descriptorBuffer, descriptorBegin, descriptorEnd);
case 'L':
return new Type(OBJECT, descriptorBuffer, descriptorBegin + 1, descriptorEnd - 1);
case '(':
return new Type(METHOD, descriptorBuffer, descriptorBegin, descriptorEnd);
default:
throw new IllegalArgumentException();
}
}
// -----------------------------------------------------------------------------------------------
// Methods to get class names, internal names or descriptors.
// -----------------------------------------------------------------------------------------------
/**
* Returns the binary name of the class corresponding to this type. This method must not be used
* on method types.
*
* @return the binary name of the class corresponding to this type.
*/
public String getClassName() {
switch (sort) {
case VOID:
return "void";
case BOOLEAN:
return "boolean";
case CHAR:
return "char";
case BYTE:
return "byte";
case SHORT:
return "short";
case INT:
return "int";
case FLOAT:
return "float";
case LONG:
return "long";
case DOUBLE:
return "double";
case ARRAY:
StringBuilder stringBuilder = new StringBuilder(getElementType().getClassName());
for (int i = getDimensions(); i > 0; --i) {
stringBuilder.append("[]");
}
return stringBuilder.toString();
case OBJECT:
case INTERNAL:
return valueBuffer.substring(valueBegin, valueEnd).replace('/', '.');
default:
throw new AssertionError();
}
}
/**
* Returns the internal name of the class corresponding to this object or array type. The internal
* name of a class is its fully qualified name (as returned by Class.getName(), where '.' are
* replaced by '/'). This method should only be used for an object or array type.
*
* @return the internal name of the class corresponding to this object type.
*/
public String getInternalName() {
return valueBuffer.substring(valueBegin, valueEnd);
}
/**
* Returns the internal name of the given class. The internal name of a class is its fully
* qualified name, as returned by Class.getName(), where '.' are replaced by '/'.
*
* @param clazz an object or array class.
* @return the internal name of the given class.
*/
public static String getInternalName(final Class<?> clazz) {
return clazz.getName().replace('.', '/');
}
/**
* Returns the descriptor corresponding to this type.
*
* @return the descriptor corresponding to this type.
*/
public String getDescriptor() {
if (sort == OBJECT) {
return valueBuffer.substring(valueBegin - 1, valueEnd + 1);
} else if (sort == INTERNAL) {
return new StringBuilder()
.append('L')
.append(valueBuffer, valueBegin, valueEnd)
.append(';')
.toString();
} else {
return valueBuffer.substring(valueBegin, valueEnd);
}
}
/**
* Returns the descriptor corresponding to the given class.
*
* @param clazz an object class, a primitive class or an array class.
* @return the descriptor corresponding to the given class.
*/
public static String getDescriptor(final Class<?> clazz) {
StringBuilder stringBuilder = new StringBuilder();
appendDescriptor(clazz, stringBuilder);
return stringBuilder.toString();
}
/**
* Returns the descriptor corresponding to the given constructor.
*
* @param constructor a {@link Constructor} object.
* @return the descriptor of the given constructor.
*/
public static String getConstructorDescriptor(final Constructor<?> constructor) {
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.append('(');
Class<?>[] parameters = constructor.getParameterTypes();
for (Class<?> parameter : parameters) {
appendDescriptor(parameter, stringBuilder);
}
return stringBuilder.append(")V").toString();
}
/**
* Returns the descriptor corresponding to the given argument and return types.
*
* @param returnType the return type of the method.
* @param argumentTypes the argument types of the method.
* @return the descriptor corresponding to the given argument and return types.
*/
public static String getMethodDescriptor(final Type returnType, final Type... argumentTypes) {
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.append('(');
for (Type argumentType : argumentTypes) {
argumentType.appendDescriptor(stringBuilder);
}
stringBuilder.append(')');
returnType.appendDescriptor(stringBuilder);
return stringBuilder.toString();
}
/**
* Returns the descriptor corresponding to the given method.
*
* @param method a {@link Method} object.
* @return the descriptor of the given method.
*/
public static String getMethodDescriptor(final Method method) {
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.append('(');
Class<?>[] parameters = method.getParameterTypes();
for (Class<?> parameter : parameters) {
appendDescriptor(parameter, stringBuilder);
}
stringBuilder.append(')');
appendDescriptor(method.getReturnType(), stringBuilder);
return stringBuilder.toString();
}
/**
* Appends the descriptor corresponding to this type to the given string buffer.
*
* @param stringBuilder the string builder to which the descriptor must be appended.
*/
private void appendDescriptor(final StringBuilder stringBuilder) {
if (sort == OBJECT) {
stringBuilder.append(valueBuffer, valueBegin - 1, valueEnd + 1);
} else if (sort == INTERNAL) {
stringBuilder.append('L').append(valueBuffer, valueBegin, valueEnd).append(';');
} else {
stringBuilder.append(valueBuffer, valueBegin, valueEnd);
}
}
/**
* Appends the descriptor of the given class to the given string builder.
*
* @param clazz the class whose descriptor must be computed.
* @param stringBuilder the string builder to which the descriptor must be appended.
*/
private static void appendDescriptor(final Class<?> clazz, final StringBuilder stringBuilder) {
Class<?> currentClass = clazz;
while (currentClass.isArray()) {
stringBuilder.append('[');
currentClass = currentClass.getComponentType();
}
if (currentClass.isPrimitive()) {
char descriptor;
if (currentClass == Integer.TYPE) {
descriptor = 'I';
} else if (currentClass == Void.TYPE) {
descriptor = 'V';
} else if (currentClass == Boolean.TYPE) {
descriptor = 'Z';
} else if (currentClass == Byte.TYPE) {
descriptor = 'B';
} else if (currentClass == Character.TYPE) {
descriptor = 'C';
} else if (currentClass == Short.TYPE) {
descriptor = 'S';
} else if (currentClass == Double.TYPE) {
descriptor = 'D';
} else if (currentClass == Float.TYPE) {
descriptor = 'F';
} else if (currentClass == Long.TYPE) {
descriptor = 'J';
} else {
throw new AssertionError();
}
stringBuilder.append(descriptor);
} else {
stringBuilder.append('L');
String name = currentClass.getName();
int nameLength = name.length();
for (int i = 0; i < nameLength; ++i) {
char car = name.charAt(i);
stringBuilder.append(car == '.' ? '/' : car);
}
stringBuilder.append(';');
}
}
// -----------------------------------------------------------------------------------------------
// Methods to get the sort, dimension, size, and opcodes corresponding to a Type or descriptor.
// -----------------------------------------------------------------------------------------------
/**
* Returns the sort of this type.
*
* @return {@link #VOID}, {@link #BOOLEAN}, {@link #CHAR}, {@link #BYTE}, {@link #SHORT}, {@link
* #INT}, {@link #FLOAT}, {@link #LONG}, {@link #DOUBLE}, {@link #ARRAY}, {@link #OBJECT} or
* {@link #METHOD}.
*/
public int getSort() {
return sort == INTERNAL ? OBJECT : sort;
}
/**
* Returns the number of dimensions of this array type. This method should only be used for an
* array type.
*
* @return the number of dimensions of this array type.
*/
public int getDimensions() {
int numDimensions = 1;
while (valueBuffer.charAt(valueBegin + numDimensions) == '[') {
numDimensions++;
}
return numDimensions;
}
/**
* Returns the size of values of this type. This method must not be used for method types.
*
* @return the size of values of this type, i.e., 2 for {@code long} and {@code double}, 0 for
* {@code void} and 1 otherwise.
*/
public int getSize() {
switch (sort) {
case VOID:
return 0;
case BOOLEAN:
case CHAR:
case BYTE:
case SHORT:
case INT:
case FLOAT:
case ARRAY:
case OBJECT:
case INTERNAL:
return 1;
case LONG:
case DOUBLE:
return 2;
default:
throw new AssertionError();
}
}
/**
* Returns the size of the arguments and of the return value of methods of this type. This method
* should only be used for method types.
*
* @return the size of the arguments of the method (plus one for the implicit this argument),
* argumentsSize, and the size of its return value, returnSize, packed into a single int i =
* {@code (argumentsSize << 2) | returnSize} (argumentsSize is therefore equal to {@code
* i >> 2}, and returnSize to {@code i & 0x03}).
*/
public int getArgumentsAndReturnSizes() {
return getArgumentsAndReturnSizes(getDescriptor());
}
/**
* Computes the size of the arguments and of the return value of a method.
*
* @param methodDescriptor a method descriptor.
* @return the size of the arguments of the method (plus one for the implicit this argument),
* argumentsSize, and the size of its return value, returnSize, packed into a single int i =
* {@code (argumentsSize << 2) | returnSize} (argumentsSize is therefore equal to {@code
* i >> 2}, and returnSize to {@code i & 0x03}).
*/
public static int getArgumentsAndReturnSizes(final String methodDescriptor) {
int argumentsSize = 1;
// Skip the first character, which is always a '('.
int currentOffset = 1;
int currentChar = methodDescriptor.charAt(currentOffset);
// Parse the argument types and compute their size, one at a each loop iteration.
while (currentChar != ')') {
if (currentChar == 'J' || currentChar == 'D') {
currentOffset++;
argumentsSize += 2;
} else {
while (methodDescriptor.charAt(currentOffset) == '[') {
currentOffset++;
}
if (methodDescriptor.charAt(currentOffset++) == 'L') {
// Skip the argument descriptor content.
currentOffset = methodDescriptor.indexOf(';', currentOffset) + 1;
}
argumentsSize += 1;
}
currentChar = methodDescriptor.charAt(currentOffset);
}
currentChar = methodDescriptor.charAt(currentOffset + 1);
if (currentChar == 'V') {
return argumentsSize << 2;
} else {
int returnSize = (currentChar == 'J' || currentChar == 'D') ? 2 : 1;
return argumentsSize << 2 | returnSize;
}
}
/**
* Returns a JVM instruction opcode adapted to this {@link Type}. This method must not be used for
* method types.
*
* @param opcode a JVM instruction opcode. This opcode must be one of ILOAD, ISTORE, IALOAD,
* IASTORE, IADD, ISUB, IMUL, IDIV, IREM, INEG, ISHL, ISHR, IUSHR, IAND, IOR, IXOR and
* IRETURN.
* @return an opcode that is similar to the given opcode, but adapted to this {@link Type}. For
* example, if this type is {@code float} and {@code opcode} is IRETURN, this method returns
* FRETURN.
*/
public int getOpcode(final int opcode) {
if (opcode == Opcodes.IALOAD || opcode == Opcodes.IASTORE) {
switch (sort) {
case BOOLEAN:
case BYTE:
return opcode + (Opcodes.BALOAD - Opcodes.IALOAD);
case CHAR:
return opcode + (Opcodes.CALOAD - Opcodes.IALOAD);
case SHORT:
return opcode + (Opcodes.SALOAD - Opcodes.IALOAD);
case INT:
return opcode;
case FLOAT:
return opcode + (Opcodes.FALOAD - Opcodes.IALOAD);
case LONG:
return opcode + (Opcodes.LALOAD - Opcodes.IALOAD);
case DOUBLE:
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