| /* |
| * ProGuard -- shrinking, optimization, obfuscation, and preverification |
| * of Java bytecode. |
| * |
| * Copyright (c) 2002-2009 Eric Lafortune (eric@graphics.cornell.edu) |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the Free |
| * Software Foundation; either version 2 of the License, or (at your option) |
| * any later version. |
| * |
| * This program 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 for |
| * more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| package proguard.classfile.util; |
| |
| import proguard.classfile.ClassConstants; |
| |
| |
| /** |
| * An <code>InternalTypeEnumeration</code> provides an enumeration of all |
| * parameter types listed in a given internal method descriptor or signature. |
| * The signature can also be a class signature. The return type of a method |
| * descriptor can retrieved separately. |
| * |
| * @author Eric Lafortune |
| */ |
| public class InternalTypeEnumeration |
| { |
| private String descriptor; |
| private int firstIndex; |
| private int lastIndex; |
| private int index; |
| |
| |
| /** |
| * Creates a new InternalTypeEnumeration for the given method descriptor. |
| */ |
| public InternalTypeEnumeration(String descriptor) |
| { |
| this.descriptor = descriptor; |
| this.firstIndex = descriptor.indexOf(ClassConstants.INTERNAL_METHOD_ARGUMENTS_OPEN); |
| this.lastIndex = descriptor.indexOf(ClassConstants.INTERNAL_METHOD_ARGUMENTS_CLOSE); |
| this.index = firstIndex + 1; |
| |
| if (lastIndex < 0) |
| { |
| lastIndex = descriptor.length(); |
| } |
| } |
| |
| |
| /** |
| * Returns the formal type parameters from the descriptor, assuming it's a |
| * method descriptor. |
| */ |
| public String formalTypeParameters() |
| { |
| return descriptor.substring(0, firstIndex); |
| } |
| |
| |
| /** |
| * Returns whether the enumeration can provide more types from the method |
| * descriptor. |
| */ |
| public boolean hasMoreTypes() |
| { |
| return index < lastIndex; |
| } |
| |
| |
| /** |
| * Returns the next type from the method descriptor. |
| */ |
| public String nextType() |
| { |
| int startIndex = index; |
| |
| skipArray(); |
| |
| char c = descriptor.charAt(index++); |
| switch (c) |
| { |
| case ClassConstants.INTERNAL_TYPE_CLASS_START: |
| case ClassConstants.INTERNAL_TYPE_GENERIC_VARIABLE_START: |
| { |
| skipClass(); |
| break; |
| } |
| case ClassConstants.INTERNAL_TYPE_GENERIC_START: |
| { |
| skipGeneric(); |
| break; |
| } |
| } |
| |
| return descriptor.substring(startIndex, index); |
| } |
| |
| |
| /** |
| * Returns the return type from the descriptor, assuming it's a method |
| * descriptor. |
| */ |
| public String returnType() |
| { |
| return descriptor.substring(lastIndex + 1); |
| } |
| |
| |
| // Small utility methods. |
| |
| private void skipArray() |
| { |
| while (descriptor.charAt(index) == ClassConstants.INTERNAL_TYPE_ARRAY) |
| { |
| index++; |
| } |
| } |
| |
| |
| private void skipClass() |
| { |
| while (true) |
| { |
| char c = descriptor.charAt(index++); |
| switch (c) |
| { |
| case ClassConstants.INTERNAL_TYPE_GENERIC_START: |
| skipGeneric(); |
| break; |
| |
| case ClassConstants.INTERNAL_TYPE_CLASS_END: |
| return; |
| } |
| } |
| } |
| |
| |
| private void skipGeneric() |
| { |
| int nestingLevel = 1; |
| |
| do |
| { |
| char c = descriptor.charAt(index++); |
| switch (c) |
| { |
| case ClassConstants.INTERNAL_TYPE_GENERIC_START: |
| nestingLevel++; |
| break; |
| |
| case ClassConstants.INTERNAL_TYPE_GENERIC_END: |
| nestingLevel--; |
| break; |
| } |
| } |
| while (nestingLevel > 0); |
| } |
| |
| |
| /** |
| * A main method for testing the type enumeration. |
| */ |
| public static void main(String[] args) |
| { |
| try |
| { |
| for (int index = 0; index < args.length; index++) |
| { |
| String descriptor = args[index]; |
| |
| System.out.println("Descriptor ["+descriptor+"]"); |
| InternalTypeEnumeration enumeration = new InternalTypeEnumeration(descriptor); |
| |
| if (enumeration.firstIndex >= 0) |
| { |
| System.out.println(" Formal type parameters ["+enumeration.formalTypeParameters()+"]"); |
| } |
| |
| while (enumeration.hasMoreTypes()) |
| { |
| System.out.println(" Type ["+enumeration.nextType()+"]"); |
| } |
| |
| if (enumeration.lastIndex < descriptor.length()) |
| { |
| System.out.println(" Return type ["+enumeration.returnType()+"]"); |
| } |
| } |
| } |
| catch (Exception ex) |
| { |
| ex.printStackTrace(); |
| } |
| } |
| } |