/*
* Bytecode Analysis Framework
* Copyright (C) 2003,2004 University of Maryland
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package edu.umd.cs.findbugs.ba;
import org.apache.bcel.classfile.JavaClass;
import org.apache.bcel.classfile.Method;
import org.apache.bcel.generic.ConstantPoolGen;
import org.apache.bcel.generic.InvokeInstruction;
import org.apache.bcel.generic.MethodGen;
import edu.umd.cs.findbugs.classfile.MethodDescriptor;
import edu.umd.cs.findbugs.internalAnnotations.DottedClassName;
/**
* Convert part or all of a Java type signature into something closer to what
* types look like in the source code. Both field and method signatures may be
* processed by this class. For a field signature, just call parseNext() once.
* For a method signature, parseNext() must be called multiple times, and the
* parens around the arguments must be skipped manually (by calling the skip()
* method).
*
* @author David Hovemeyer
*/
public class SignatureConverter {
private String signature;
/**
* Constructor.
*
* @param signature
* the field or method signature to convert
*/
public SignatureConverter(String signature) {
this.signature = signature;
}
/**
* Get the first character of the remaining part of the signature.
*/
public char getFirst() {
return signature.charAt(0);
}
/**
* Skip the first character of the remaining part of the signature.
*/
public void skip() {
signature = signature.substring(1);
}
/**
* Parse a single type out of the signature, starting at the beginning of
* the remaining part of the signature. For example, if the first character
* of the remaining part is "I", then this method will return "int", and the
* "I" will be consumed. Arrays, reference types, and basic types are all
* handled.
*
* @return the parsed type string
*/
public String parseNext() {
StringBuilder result = new StringBuilder();
if (signature.startsWith("[")) {
int dimensions = 0;
do {
++dimensions;
signature = signature.substring(1);
} while (signature.charAt(0) == '[');
result.append(parseNext());
while (dimensions-- > 0) {
result.append("[]");
}
} else if (signature.startsWith("L")) {
int semi = signature.indexOf(';');
if (semi < 0)
throw new IllegalStateException("missing semicolon in signature " + signature);
result.append(signature.substring(1, semi).replace('/', '.'));
signature = signature.substring(semi + 1);
} else {
switch (signature.charAt(0)) {
case 'B':
result.append("byte");
break;
case 'C':
result.append("char");
break;
case 'D':
result.append("double");
break;
case 'F':
result.append("float");
break;
case 'I':
result.append("int");
break;
case 'J':
result.append("long");
break;
case 'S':
result.append("short");
break;
case 'Z':
result.append("boolean");
break;
case 'V':
result.append("void");
break;
default:
throw new IllegalArgumentException("bad signature " + signature);
}
skip();
}
return result.toString();
}
/**
* Convenience method for generating a method signature in human readable
* form.
*
* @param javaClass
* the class
* @param method
* the method
*/
public static String convertMethodSignature(JavaClass javaClass, Method method) {
return convertMethodSignature(javaClass.getClassName(), method.getName(), method.getSignature());
}
/**
* Convenience method for generating a method signature in human readable
* form.
*
* @param methodGen
* the method to produce a method signature for
*/
public static String convertMethodSignature(MethodGen methodGen) {
return convertMethodSignature(methodGen.getClassName(), methodGen.getName(), methodGen.getSignature());
}
/**
* Convenience method for generating a method signature in human readable
* form.
*
* @param inv
* an InvokeInstruction
* @param cpg
* the ConstantPoolGen for the class the instruction belongs to
*/
public static String convertMethodSignature(InvokeInstruction inv, ConstantPoolGen cpg) {
return convertMethodSignature(inv.getClassName(cpg), inv.getName(cpg), inv.getSignature(cpg));
}
/**
* Convenience method for generating a method signature in human readable
* form.
*
* @param className
* name of the class containing the method
* @param methodName
* the name of the method
* @param methodSig
* the signature of the method
*/
public static String convertMethodSignature(String className, String methodName, String methodSig) {
return convertMethodSignature(className, methodName, methodSig, "");
}
/**
* Convenience method for generating a method signature in human readable
* form.
*
* @param xmethod
* an XMethod
* @return the formatted version of that signature
*/
public static String convertMethodSignature(XMethod xmethod) {
@DottedClassName
String className = xmethod.getClassName();
assert className.indexOf('/') == -1;
return convertMethodSignature(className, xmethod.getName(), xmethod.getSignature());
}
/**
* Convenience method for generating a method signature in human readable
* form.
*
* @param methodDescriptor
* a MethodDescriptor
* @return the formatted version of that signature
*/
public static String convertMethodSignature(MethodDescriptor methodDescriptor) {
return convertMethodSignature(methodDescriptor.getClassDescriptor().toDottedClassName(), methodDescriptor.getName(),
methodDescriptor.getSignature());
}
/**
* Convenience method for generating a method signature in human readable
* form.
*
* @param className
* name of the class containing the method
* @param methodName
* the name of the method
* @param methodSig
* the signature of the method
* @param pkgName
* the name of the package the method is in (used to shorten
* class names)
*/
public static String convertMethodSignature(String className, String methodName, String methodSig, String pkgName) {
StringBuilder args = new StringBuilder();
SignatureConverter converter = new SignatureConverter(methodSig);
converter.skip();
args.append('(');
while (converter.getFirst() != ')') {
if (args.length() > 1)
args.append(", ");
args.append(shorten(pkgName, converter.parseNext()));
}
converter.skip();
args.append(')');
// Ignore return type
StringBuilder result = new StringBuilder();
result.append(className);
result.append('.');
result.append(methodName);
result.append(args.toString());
return result.toString();
}
/**
* Convenience method for converting a single signature component to
* human-readable form.
*
* @param signature
* the signature
*/
public static String convert(String signature) {
return new SignatureConverter(signature).parseNext();
}
public static String shorten(String pkgName, String typeName) {
int index = typeName.lastIndexOf('.');
if (index >= 0) {
String otherPkg = typeName.substring(0, index);
if (otherPkg.equals(pkgName) || otherPkg.equals("java.lang"))
typeName = typeName.substring(index + 1);
}
return typeName;
}
}
// vim:ts=4