| /* |
| * Copyright (C) 2008 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.google.gson; |
| |
| import java.lang.reflect.Field; |
| import java.util.Locale; |
| |
| /** |
| * An enumeration that defines a few standard naming conventions for JSON field names. |
| * This enumeration should be used in conjunction with {@link com.google.gson.GsonBuilder} |
| * to configure a {@link com.google.gson.Gson} instance to properly translate Java field |
| * names into the desired JSON field names. |
| * |
| * @author Inderjeet Singh |
| * @author Joel Leitch |
| */ |
| public enum FieldNamingPolicy implements FieldNamingStrategy { |
| |
| /** |
| * Using this naming policy with Gson will ensure that the field name is |
| * unchanged. |
| */ |
| IDENTITY() { |
| @Override public String translateName(Field f) { |
| return f.getName(); |
| } |
| }, |
| |
| /** |
| * Using this naming policy with Gson will ensure that the first "letter" of the Java |
| * field name is capitalized when serialized to its JSON form. |
| * |
| * <p>Here's a few examples of the form "Java Field Name" ---> "JSON Field Name":</p> |
| * <ul> |
| * <li>someFieldName ---> SomeFieldName</li> |
| * <li>_someFieldName ---> _SomeFieldName</li> |
| * </ul> |
| */ |
| UPPER_CAMEL_CASE() { |
| @Override public String translateName(Field f) { |
| return upperCaseFirstLetter(f.getName()); |
| } |
| }, |
| |
| /** |
| * Using this naming policy with Gson will ensure that the first "letter" of the Java |
| * field name is capitalized when serialized to its JSON form and the words will be |
| * separated by a space. |
| * |
| * <p>Here's a few examples of the form "Java Field Name" ---> "JSON Field Name":</p> |
| * <ul> |
| * <li>someFieldName ---> Some Field Name</li> |
| * <li>_someFieldName ---> _Some Field Name</li> |
| * </ul> |
| * |
| * @since 1.4 |
| */ |
| UPPER_CAMEL_CASE_WITH_SPACES() { |
| @Override public String translateName(Field f) { |
| return upperCaseFirstLetter(separateCamelCase(f.getName(), " ")); |
| } |
| }, |
| |
| /** |
| * Using this naming policy with Gson will modify the Java Field name from its camel cased |
| * form to a lower case field name where each word is separated by an underscore (_). |
| * |
| * <p>Here's a few examples of the form "Java Field Name" ---> "JSON Field Name":</p> |
| * <ul> |
| * <li>someFieldName ---> some_field_name</li> |
| * <li>_someFieldName ---> _some_field_name</li> |
| * <li>aStringField ---> a_string_field</li> |
| * <li>aURL ---> a_u_r_l</li> |
| * </ul> |
| */ |
| LOWER_CASE_WITH_UNDERSCORES() { |
| @Override public String translateName(Field f) { |
| return separateCamelCase(f.getName(), "_").toLowerCase(Locale.ENGLISH); |
| } |
| }, |
| |
| /** |
| * Using this naming policy with Gson will modify the Java Field name from its camel cased |
| * form to a lower case field name where each word is separated by a dash (-). |
| * |
| * <p>Here's a few examples of the form "Java Field Name" ---> "JSON Field Name":</p> |
| * <ul> |
| * <li>someFieldName ---> some-field-name</li> |
| * <li>_someFieldName ---> _some-field-name</li> |
| * <li>aStringField ---> a-string-field</li> |
| * <li>aURL ---> a-u-r-l</li> |
| * </ul> |
| * Using dashes in JavaScript is not recommended since dash is also used for a minus sign in |
| * expressions. This requires that a field named with dashes is always accessed as a quoted |
| * property like {@code myobject['my-field']}. Accessing it as an object field |
| * {@code myobject.my-field} will result in an unintended javascript expression. |
| * @since 1.4 |
| */ |
| LOWER_CASE_WITH_DASHES() { |
| @Override public String translateName(Field f) { |
| return separateCamelCase(f.getName(), "-").toLowerCase(Locale.ENGLISH); |
| } |
| }; |
| |
| /** |
| * Converts the field name that uses camel-case define word separation into |
| * separate words that are separated by the provided {@code separatorString}. |
| */ |
| private static String separateCamelCase(String name, String separator) { |
| StringBuilder translation = new StringBuilder(); |
| for (int i = 0; i < name.length(); i++) { |
| char character = name.charAt(i); |
| if (Character.isUpperCase(character) && translation.length() != 0) { |
| translation.append(separator); |
| } |
| translation.append(character); |
| } |
| return translation.toString(); |
| } |
| |
| /** |
| * Ensures the JSON field names begins with an upper case letter. |
| */ |
| private static String upperCaseFirstLetter(String name) { |
| StringBuilder fieldNameBuilder = new StringBuilder(); |
| int index = 0; |
| char firstCharacter = name.charAt(index); |
| |
| while (index < name.length() - 1) { |
| if (Character.isLetter(firstCharacter)) { |
| break; |
| } |
| |
| fieldNameBuilder.append(firstCharacter); |
| firstCharacter = name.charAt(++index); |
| } |
| |
| if (index == name.length()) { |
| return fieldNameBuilder.toString(); |
| } |
| |
| if (!Character.isUpperCase(firstCharacter)) { |
| String modifiedTarget = modifyString(Character.toUpperCase(firstCharacter), name, ++index); |
| return fieldNameBuilder.append(modifiedTarget).toString(); |
| } else { |
| return name; |
| } |
| } |
| |
| private static String modifyString(char firstCharacter, String srcString, int indexOfSubstring) { |
| return (indexOfSubstring < srcString.length()) |
| ? firstCharacter + srcString.substring(indexOfSubstring) |
| : String.valueOf(firstCharacter); |
| } |
| } |