1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.ant; 18 19 import org.apache.tools.ant.BuildException; 20 import org.apache.tools.ant.Task; 21 import org.apache.tools.ant.taskdefs.Sequential; 22 import org.apache.tools.ant.taskdefs.condition.And; 23 24 /** 25 * If (condition) then: {@link Sequential} else: {@link Sequential}. 26 * 27 * In XML: 28 * <if condition="${prop with a boolean value}"> 29 * <then> 30 * </then> 31 * <else> 32 * </else> 33 * </if> 34 * 35 * or 36 * 37 * <if> 38 * <condition> 39 * ... 40 * </condition> 41 * <then> 42 * </then> 43 * <else> 44 * </else> 45 * </if> 46 * 47 * both <then> and <else> behave like <sequential>. 48 * <condition> behaves like an <and> condition. 49 * 50 * The presence of both <then> and <else> is not required, but one of them must be present. 51 * <if condition="${some.condition}"> 52 * <else> 53 * </else> 54 * </if> 55 * is perfectly valid. 56 * 57 */ 58 public class IfElseTask extends Task { 59 60 private boolean mCondition; 61 private boolean mConditionIsSet = false; 62 private And mAnd; 63 private Sequential mThen; 64 private Sequential mElse; 65 66 /** 67 * Sets the condition value 68 */ 69 public void setCondition(boolean condition) { 70 mCondition = condition; 71 mConditionIsSet = true; 72 } 73 74 /** 75 * Creates and returns the <condition> node which is basically a <and>. 76 */ 77 public Object createCondition() { 78 if (mConditionIsSet) { 79 throw new BuildException("Cannot use both condition attribute and <condition> element"); 80 } 81 82 mAnd = new And(); 83 mAnd.setProject(getProject()); 84 return mAnd; 85 } 86 87 /** 88 * Creates and returns the <then> {@link Sequential} 89 */ 90 public Object createThen() { 91 mThen = new Sequential(); 92 return mThen; 93 } 94 95 /** 96 * Creates and returns the <else> {@link Sequential} 97 */ 98 public Object createElse() { 99 mElse = new Sequential(); 100 return mElse; 101 } 102 103 @Override 104 public void execute() throws BuildException { 105 if (mConditionIsSet == false && mAnd == null) { 106 throw new BuildException("condition attribute or element must be set."); 107 } 108 109 if (mAnd != null) { 110 mCondition = mAnd.eval(); 111 } 112 113 // need at least one. 114 if (mThen == null && mElse == null) { 115 throw new BuildException("Need at least <then> or <else>"); 116 } 117 118 if (mCondition) { 119 if (mThen != null) { 120 mThen.execute(); 121 } 122 } else { 123 if (mElse != null) { 124 mElse.execute(); 125 } 126 } 127 } 128 } 129