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AspectJ tools most notably contains the AspectJ compiler (AJC). AJC applies aspects to Java classes during
compilation, fully replacing Javac for plain Java classes and also compiling native AspectJ or annotation-based
@AspectJ syntax. Furthermore, AJC can weave aspects into existing class files in a post-compile binary weaving step.
This library is a superset of AspectJ weaver and hence also of AspectJ runtime.
// 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 aj.org.objectweb.asm.signature;
/**
* A parser for signature literals, as defined in the Java Virtual Machine Specification (JVMS), to
* visit them with a SignatureVisitor.
*
* @see JVMS
* 4.7.9.1
* @author Thomas Hallgren
* @author Eric Bruneton
*/
public class SignatureReader {
/** The JVMS signature to be read. */
private final String signatureValue;
/**
* Constructs a {@link SignatureReader} for the given signature.
*
* @param signature A JavaTypeSignature, ClassSignature or MethodSignature.
*/
public SignatureReader(final String signature) {
this.signatureValue = signature;
}
/**
* Makes the given visitor visit the signature of this {@link SignatureReader}. This signature is
* the one specified in the constructor (see {@link #SignatureReader}). This method is intended to
* be called on a {@link SignatureReader} that was created using a ClassSignature (such as
* the signature parameter of the {@link aj.org.objectweb.asm.ClassVisitor#visit}
* method) or a MethodSignature (such as the signature parameter of the {@link
* aj.org.objectweb.asm.ClassVisitor#visitMethod} method).
*
* @param signatureVistor the visitor that must visit this signature.
*/
public void accept(final SignatureVisitor signatureVistor) {
String signature = this.signatureValue;
int length = signature.length();
int offset; // Current offset in the parsed signature (parsed from left to right).
char currentChar; // The signature character at 'offset', or just before.
// If the signature starts with '<', it starts with TypeParameters, i.e. a formal type parameter
// identifier, followed by one or more pair ':',ReferenceTypeSignature (for its class bound and
// interface bounds).
if (signature.charAt(0) == '<') {
// Invariant: offset points to the second character of a formal type parameter name at the
// beginning of each iteration of the loop below.
offset = 2;
do {
// The formal type parameter name is everything between offset - 1 and the first ':'.
int classBoundStartOffset = signature.indexOf(':', offset);
signatureVistor.visitFormalTypeParameter(
signature.substring(offset - 1, classBoundStartOffset));
// If the character after the ':' class bound marker is not the start of a
// ReferenceTypeSignature, it means the class bound is empty (which is a valid case).
offset = classBoundStartOffset + 1;
currentChar = signature.charAt(offset);
if (currentChar == 'L' || currentChar == '[' || currentChar == 'T') {
offset = parseType(signature, offset, signatureVistor.visitClassBound());
}
// While the character after the class bound or after the last parsed interface bound
// is ':', we need to parse another interface bound.
while ((currentChar = signature.charAt(offset++)) == ':') {
offset = parseType(signature, offset, signatureVistor.visitInterfaceBound());
}
// At this point a TypeParameter has been fully parsed, and we need to parse the next one
// (note that currentChar is now the first character of the next TypeParameter, and that
// offset points to the second character), unless the character just after this
// TypeParameter signals the end of the TypeParameters.
} while (currentChar != '>');
} else {
offset = 0;
}
// If the (optional) TypeParameters is followed by '(' this means we are parsing a
// MethodSignature, which has JavaTypeSignature type inside parentheses, followed by a Result
// type and optional ThrowsSignature types.
if (signature.charAt(offset) == '(') {
offset++;
while (signature.charAt(offset) != ')') {
offset = parseType(signature, offset, signatureVistor.visitParameterType());
}
// Use offset + 1 to skip ')'.
offset = parseType(signature, offset + 1, signatureVistor.visitReturnType());
while (offset < length) {
// Use offset + 1 to skip the first character of a ThrowsSignature, i.e. '^'.
offset = parseType(signature, offset + 1, signatureVistor.visitExceptionType());
}
} else {
// Otherwise we are parsing a ClassSignature (by hypothesis on the method input), which has
// one or more ClassTypeSignature for the super class and the implemented interfaces.
offset = parseType(signature, offset, signatureVistor.visitSuperclass());
while (offset < length) {
offset = parseType(signature, offset, signatureVistor.visitInterface());
}
}
}
/**
* Makes the given visitor visit the signature of this {@link SignatureReader}. This signature is
* the one specified in the constructor (see {@link #SignatureReader}). This method is intended to
* be called on a {@link SignatureReader} that was created using a JavaTypeSignature, such
* as the signature parameter of the {@link
* aj.org.objectweb.asm.ClassVisitor#visitField} or {@link
* aj.org.objectweb.asm.MethodVisitor#visitLocalVariable} methods.
*
* @param signatureVisitor the visitor that must visit this signature.
*/
public void acceptType(final SignatureVisitor signatureVisitor) {
parseType(signatureValue, 0, signatureVisitor);
}
/**
* Parses a JavaTypeSignature and makes the given visitor visit it.
*
* @param signature a string containing the signature that must be parsed.
* @param startOffset index of the first character of the signature to parsed.
* @param signatureVisitor the visitor that must visit this signature.
* @return the index of the first character after the parsed signature.
*/
private static int parseType(
final String signature, final int startOffset, final SignatureVisitor signatureVisitor) {
int offset = startOffset; // Current offset in the parsed signature.
char currentChar = signature.charAt(offset++); // The signature character at 'offset'.
// Switch based on the first character of the JavaTypeSignature, which indicates its kind.
switch (currentChar) {
case 'Z':
case 'C':
case 'B':
case 'S':
case 'I':
case 'F':
case 'J':
case 'D':
case 'V':
// Case of a BaseType or a VoidDescriptor.
signatureVisitor.visitBaseType(currentChar);
return offset;
case '[':
// Case of an ArrayTypeSignature, a '[' followed by a JavaTypeSignature.
return parseType(signature, offset, signatureVisitor.visitArrayType());
case 'T':
// Case of TypeVariableSignature, an identifier between 'T' and ';'.
int endOffset = signature.indexOf(';', offset);
signatureVisitor.visitTypeVariable(signature.substring(offset, endOffset));
return endOffset + 1;
case 'L':
// Case of a ClassTypeSignature, which ends with ';'.
// These signatures have a main class type followed by zero or more inner class types
// (separated by '.'). Each can have type arguments, inside '<' and '>'.
int start = offset; // The start offset of the currently parsed main or inner class name.
boolean visited = false; // Whether the currently parsed class name has been visited.
boolean inner = false; // Whether we are currently parsing an inner class type.
// Parses the signature, one character at a time.
while (true) {
currentChar = signature.charAt(offset++);
if (currentChar == '.' || currentChar == ';') {
// If a '.' or ';' is encountered, this means we have fully parsed the main class name
// or an inner class name. This name may already have been visited it is was followed by
// type arguments between '<' and '>'. If not, we need to visit it here.
if (!visited) {
String name = signature.substring(start, offset - 1);
if (inner) {
signatureVisitor.visitInnerClassType(name);
} else {
signatureVisitor.visitClassType(name);
}
}
// If we reached the end of the ClassTypeSignature return, otherwise start the parsing
// of a new class name, which is necessarily an inner class name.
if (currentChar == ';') {
signatureVisitor.visitEnd();
break;
}
start = offset;
visited = false;
inner = true;
} else if (currentChar == '<') {
// If a '<' is encountered, this means we have fully parsed the main class name or an
// inner class name, and that we now need to parse TypeArguments. First, we need to
// visit the parsed class name.
String name = signature.substring(start, offset - 1);
if (inner) {
signatureVisitor.visitInnerClassType(name);
} else {
signatureVisitor.visitClassType(name);
}
visited = true;
// Now, parse the TypeArgument(s), one at a time.
while ((currentChar = signature.charAt(offset)) != '>') {
switch (currentChar) {
case '*':
// Unbounded TypeArgument.
++offset;
signatureVisitor.visitTypeArgument();
break;
case '+':
case '-':
// Extends or Super TypeArgument. Use offset + 1 to skip the '+' or '-'.
offset =
parseType(
signature, offset + 1, signatureVisitor.visitTypeArgument(currentChar));
break;
default:
// Instanceof TypeArgument. The '=' is implicit.
offset = parseType(signature, offset, signatureVisitor.visitTypeArgument('='));
break;
}
}
}
}
return offset;
default:
throw new IllegalArgumentException();
}
}
}