1 /* 2 * Copyright (C) 2007 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.ide.common.resources.configuration; 18 19 20 /** 21 * Base class for resource qualifiers. 22 * <p/>The resource qualifier classes are designed as immutable. 23 */ 24 public abstract class ResourceQualifier implements Comparable<ResourceQualifier> { 25 26 /** 27 * Returns the human readable name of the qualifier. 28 */ getName()29 public abstract String getName(); 30 31 /** 32 * Returns a shorter human readable name for the qualifier. 33 * @see #getName() 34 */ getShortName()35 public abstract String getShortName(); 36 37 /** 38 * Returns when this qualifier was added to Android. 39 */ since()40 public abstract int since(); 41 42 /** 43 * Whether this qualifier is deprecated. 44 */ deprecated()45 public boolean deprecated() { 46 return false; 47 } 48 49 /** 50 * Returns whether the qualifier has a valid filter value. 51 */ isValid()52 public abstract boolean isValid(); 53 54 /** 55 * Returns whether the qualifier has a fake value. 56 * <p/>Fake values are used internally and should not be used as real qualifier value. 57 */ hasFakeValue()58 public abstract boolean hasFakeValue(); 59 60 /** 61 * Check if the value is valid for this qualifier, and if so sets the value 62 * into a Folder Configuration. 63 * @param value The value to check and set. Must not be null. 64 * @param config The folder configuration to receive the value. Must not be null. 65 * @return true if the value was valid and was set. 66 */ checkAndSet(String value, FolderConfiguration config)67 public abstract boolean checkAndSet(String value, FolderConfiguration config); 68 69 /** 70 * Returns a string formated to be used in a folder name. 71 * <p/>This is declared as abstract to force children classes to implement it. 72 */ getFolderSegment()73 public abstract String getFolderSegment(); 74 75 /** 76 * Returns whether the given qualifier is a match for the receiver. 77 * <p/>The default implementation returns the result of {@link #equals(Object)}. 78 * <p/>Children class that re-implements this must implement 79 * {@link #isBetterMatchThan(ResourceQualifier, ResourceQualifier)} too. 80 * @param qualifier the reference qualifier 81 * @return true if the receiver is a match. 82 */ isMatchFor(ResourceQualifier qualifier)83 public boolean isMatchFor(ResourceQualifier qualifier) { 84 return equals(qualifier); 85 } 86 87 /** 88 * Returns true if the receiver is a better match for the given <var>reference</var> than 89 * the given <var>compareTo</var> comparable. 90 * @param compareTo The {@link ResourceQualifier} to compare to. Can be null, in which 91 * case the method must return <code>true</code>. 92 * @param reference The reference qualifier value for which the match is. 93 * @return true if the receiver is a better match. 94 */ isBetterMatchThan(ResourceQualifier compareTo, ResourceQualifier reference)95 public boolean isBetterMatchThan(ResourceQualifier compareTo, ResourceQualifier reference) { 96 // the default is to always return false. This gives less overhead than always returning 97 // true, as it would only compare same values anyway. 98 return false; 99 } 100 101 @Override toString()102 public String toString() { 103 return getFolderSegment(); 104 } 105 106 /** 107 * Returns a string formatted for display purpose. 108 */ getShortDisplayValue()109 public abstract String getShortDisplayValue(); 110 111 /** 112 * Returns a string formatted for display purpose. 113 */ getLongDisplayValue()114 public abstract String getLongDisplayValue(); 115 116 /** 117 * Returns <code>true</code> if both objects are equal. 118 * <p/>This is declared as abstract to force children classes to implement it. 119 */ 120 @Override equals(Object object)121 public abstract boolean equals(Object object); 122 123 /** 124 * Returns a hash code value for the object. 125 * <p/>This is declared as abstract to force children classes to implement it. 126 */ 127 @Override hashCode()128 public abstract int hashCode(); 129 130 @Override compareTo(ResourceQualifier o)131 public final int compareTo(ResourceQualifier o) { 132 return toString().compareTo(o.toString()); 133 } 134 } 135