001 /* 002 * Copyright (C) 2006-2007 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017 package org.codehaus.gmaven.runtime.support.stubgen.parser; 018 019 import java.lang.reflect.Field; 020 import java.lang.reflect.Modifier; 021 import java.util.LinkedHashMap; 022 import java.util.Map; 023 024 /** 025 * Discovers token names and values from a class dynamically. 026 * 027 * @author <a href="mailto:jason@planet57.com">Jason Dillon</a> 028 * @version $Id: DynamicTokens.java 18 2009-07-16 09:39:40Z user57 $ 029 */ 030 public class DynamicTokens 031 implements Tokens 032 { 033 /** Maps token name to value. */ 034 private final Map names = new LinkedHashMap(); 035 036 /** Maps token value to name. */ 037 private final Map values = new LinkedHashMap(); 038 039 public DynamicTokens(final Class type) { 040 assert type != null; 041 042 try { 043 discover(type); 044 } 045 catch (IllegalAccessException e) { 046 throw new RuntimeException(e); 047 } 048 } 049 050 private void discover(final Class type) throws IllegalAccessException { 051 assert type != null; 052 053 Field[] fields = type.getDeclaredFields(); 054 055 for (int i = 0; i < fields.length; i++) { 056 discover(fields[i]); 057 } 058 } 059 060 private void discover(final Field field) throws IllegalAccessException { 061 assert field != null; 062 063 int mod = field.getModifiers(); 064 065 if (Modifier.isPublic(mod) && Modifier.isStatic(mod) && Modifier.isFinal(mod)) { 066 String name = field.getName(); 067 Class type = field.getType(); 068 Object value = field.get(type); 069 070 // Token types are only numbers, so ignore everything else 071 if (value instanceof Number) { 072 names.put(name, value); 073 values.put(value, name); 074 } 075 } 076 } 077 078 public int value(final String name) { 079 assert name != null; 080 081 Number value = (Number) names.get(name); 082 if (value == null) { 083 throw new IllegalArgumentException("Unknown token name: " + name); 084 } 085 086 return value.intValue(); 087 } 088 089 public String name(final int value) { 090 String name = (String)values.get(new Integer(value)); 091 if (name == null) { 092 throw new IllegalArgumentException("Unknown token value: " + value); 093 } 094 095 return name; 096 } 097 }