Java tutorial
//package com.java2s; //License from project: Open Source License import java.util.Base64; import java.util.Iterator; import java.util.Map.Entry; import com.google.gson.JsonArray; import com.google.gson.JsonElement; import com.google.gson.JsonObject; import com.google.gson.JsonPrimitive; public class Main { private static final String CDATA_CLOSE = "]]>"; private static final String CDATA_OPEN = "<![CDATA["; private static final String ESQ = "=\""; private static final String SPACE = " "; private static final String EQ = "\""; private static final String EMPTY = ""; private static final String ATTR_TEXT = "#text"; private static final String ATTR_CDATA = "#cdata-section"; private static final String LTS = "</"; private static final String GT = ">"; private static final String LT = "<"; private static void serializeObjectAsXml(JsonObject objectJson, StringBuffer buff) { Iterator elements = objectJson.entrySet().iterator(); while (elements.hasNext()) { Entry entry = (Entry) elements.next(); Object key = entry.getKey(); Object value = entry.getValue(); if (value instanceof JsonObject) { buff.append(LT).append(key); serializeObjectAttributes((JsonObject) value, buff); buff.append(GT); serializeObjectAsXml((JsonObject) value, buff); buff.append(LTS).append(key).append(GT); } else if (value instanceof JsonArray) { serializeArrayAsXml(buff, key, value); } else if (value instanceof JsonPrimitive) { if (ATTR_TEXT.equals(key)) { buff.append(value.toString().replace(EQ, EMPTY)); } else if (ATTR_CDATA.equals(key)) { buff.append(CDATA_OPEN) .append(new String(Base64.getDecoder().decode(value.toString().replace(EQ, EMPTY)))) .append(CDATA_CLOSE); } else { if (!key.toString().startsWith("-")) { buff.append(LT).append(key.toString()).append(GT) .append(value.toString().replace(EQ, EMPTY)).append(LTS).append(key.toString()) .append(GT); } } } else { System.err.println("ERROR: unhandled element"); } } } private static void serializeObjectAttributes(JsonObject objectJson, StringBuffer buff) { Iterator elements = objectJson.entrySet().iterator(); while (elements.hasNext()) { Entry entry = (Entry) elements.next(); Object key = entry.getKey(); Object value = entry.getValue(); if (value instanceof JsonPrimitive) { if (key.toString().startsWith("-")) { buff.append(SPACE).append(key.toString().substring(1)).append(ESQ) .append(value.toString().replace(EQ, EMPTY)).append(EQ); } } } } private static void serializeArrayAsXml(StringBuffer buff, Object key, Object value) { JsonArray array = (JsonArray) value; for (int i = 0; i < array.size(); i++) { JsonElement elementJson = array.get(i); if (elementJson instanceof JsonObject) { buff.append(LT).append(key); serializeObjectAttributes((JsonObject) elementJson, buff); buff.append(GT); serializeObjectAsXml((JsonObject) elementJson, buff); buff.append(LTS).append(key).append(GT); } else if (elementJson instanceof JsonArray) { serializeArrayAsXml(buff, key, elementJson); } else if (elementJson instanceof JsonPrimitive) { JsonPrimitive elementPrimitive = (JsonPrimitive) elementJson; if (ATTR_TEXT.equals(key)) { buff.append(elementPrimitive.toString().replace(EQ, EMPTY)); } else if (ATTR_CDATA.equals(key)) { buff.append(CDATA_OPEN) .append(new String( Base64.getDecoder().decode(elementPrimitive.toString().replace(EQ, EMPTY)))) .append(CDATA_CLOSE); } else { // System.err.println("ERROR: content attributes must be #text"); buff.append(LT).append(key); buff.append(GT); buff.append(elementPrimitive.toString().replace(EQ, EMPTY)); buff.append(LTS).append(key).append(GT); } } } } }