| /* |
| * 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 are 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 are 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 an upper case field name where each word is separated by an underscore (_). |
| * |
| * <p>Here are 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> |
| */ |
| UPPER_CASE_WITH_UNDERSCORES() { |
| @Override public String translateName(Field f) { |
| return separateCamelCase(f.getName(), '_').toUpperCase(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 an underscore (_). |
| * |
| * <p>Here are 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 are 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); |
| } |
| }, |
| |
| /** |
| * 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 dot (.). |
| * |
| * <p>Here are 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 dots in JavaScript is not recommended since dot is also used for a member sign in |
| * expressions. This requires that a field named with dots 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 2.8 |
| */ |
| LOWER_CASE_WITH_DOTS() { |
| @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 separator}. |
| */ |
| static String separateCamelCase(String name, char separator) { |
| StringBuilder translation = new StringBuilder(); |
| for (int i = 0, length = name.length(); i < 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. |
| */ |
| static String upperCaseFirstLetter(String s) { |
| int length = s.length(); |
| for (int i = 0; i < length; i++) { |
| char c = s.charAt(i); |
| if (Character.isLetter(c)) { |
| if (Character.isUpperCase(c)) { |
| return s; |
| } |
| |
| char uppercased = Character.toUpperCase(c); |
| // For leading letter only need one substring |
| if (i == 0) { |
| return uppercased + s.substring(1); |
| } else { |
| return s.substring(0, i) + uppercased + s.substring(i + 1); |
| } |
| } |
| } |
| |
| return s; |
| } |
| } |