1 /* 2 * Copyright (C) 2015 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 android.databinding.tool.util; 18 19 import android.databinding.tool.reflection.Callable; 20 21 /** 22 * Central place to convert method/field names to BR observable fields 23 */ 24 public class BrNameUtil { stripPrefixFromField(String name)25 private static String stripPrefixFromField(String name) { 26 if (name.length() >= 2) { 27 char firstChar = name.charAt(0); 28 char secondChar = name.charAt(1); 29 if (name.length() > 2 && firstChar == 'm' && secondChar == '_') { 30 char thirdChar = name.charAt(2); 31 if (Character.isJavaIdentifierStart(thirdChar)) { 32 return "" + Character.toLowerCase(thirdChar) + 33 name.subSequence(3, name.length()); 34 } 35 } else if ((firstChar == 'm' && Character.isUpperCase(secondChar)) || 36 (firstChar == '_' && Character.isJavaIdentifierStart(secondChar))) { 37 return "" + Character.toLowerCase(secondChar) + name.subSequence(2, name.length()); 38 } 39 } 40 return name; 41 } 42 brKey(Callable callable)43 public static String brKey(Callable callable) { 44 if (callable.type == Callable.Type.FIELD) { 45 return stripPrefixFromField(callable.name); 46 } 47 CharSequence propertyName; 48 final String name = callable.name; 49 if (isGetter(callable) || isSetter(callable)) { 50 propertyName = name.subSequence(3, name.length()); 51 } else if (isBooleanGetter(callable)) { 52 propertyName = name.subSequence(2, name.length()); 53 } else { 54 L.e("@Bindable associated with method must follow JavaBeans convention %s", callable); 55 return null; 56 } 57 char firstChar = propertyName.charAt(0); 58 return "" + Character.toLowerCase(firstChar) + 59 propertyName.subSequence(1, propertyName.length()); 60 } 61 isGetter(Callable callable)62 private static boolean isGetter(Callable callable) { 63 return prefixes(callable.name, "get") && 64 Character.isJavaIdentifierStart(callable.name.charAt(3)) && 65 callable.getParameterCount() == 0 && 66 !callable.resolvedType.isVoid(); 67 } 68 isSetter(Callable callable)69 private static boolean isSetter(Callable callable) { 70 return prefixes(callable.name, "set") && 71 Character.isJavaIdentifierStart(callable.name.charAt(3)) && 72 callable.getParameterCount() == 1 && 73 callable.resolvedType.isVoid(); 74 } 75 isBooleanGetter(Callable callable)76 private static boolean isBooleanGetter(Callable callable) { 77 return prefixes(callable.name, "is") && 78 Character.isJavaIdentifierStart(callable.name.charAt(2)) && 79 callable.getParameterCount() == 0 && 80 callable.resolvedType.isBoolean(); 81 } 82 prefixes(CharSequence sequence, String prefix)83 private static boolean prefixes(CharSequence sequence, String prefix) { 84 boolean prefixes = false; 85 if (sequence.length() > prefix.length()) { 86 int count = prefix.length(); 87 prefixes = true; 88 for (int i = 0; i < count; i++) { 89 if (sequence.charAt(i) != prefix.charAt(i)) { 90 prefixes = false; 91 break; 92 } 93 } 94 } 95 return prefixes; 96 } 97 } 98