JsonPluginsUtil

package utils;

import java.lang.reflect.Field;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import net.sf.json.JsonConfig;
import net.sf.json.processors.JsonValueProcessor;
import net.sf.json.util.CycleDetectionStrategy;

/**
* Json与javaBean之间的转换工具类 {@code 现使用json-lib组件实现
* 需要
* json-lib-2.4-jdk15.jar
* ezmorph-1.0.6.jar
* commons-collections-3.1.jar
* commons-lang-2.0.jar
* 支持
* }
*/
public class JsonPluginsUtil {

/**
* 从一个JSON 对象字符格式中得到一个java对象
*
* @param jsonString
* @param beanCalss
* @return
*/
@SuppressWarnings("unchecked")
public static <T> T jsonToBean(String jsonString, Class<T> beanCalss) {
JSONObject jsonObject = JSONObject.fromObject(jsonString);
T bean = (T) JSONObject.toBean(jsonObject, beanCalss);
return bean;
}

/**
* 将java对象转换成json字符串
*
* @param bean
* @return
*/
public static String beanToJson(Object bean) {
JSONObject json = JSONObject.fromObject(bean);
return json.toString();
}

/**
* 将java对象转换成json字符串
*
* @param bean
* _nory_changes 表示不需要传化的属性，如果第三个参数nory为false，则表示排除第二个参数的转换
* @return
*/
public static String beanToJson(Object bean, String[] _nory_changes,
boolean nory) {
JSONObject json = null;
if (nory) {// 转换_nory_changes里的属性

Field[] fields = bean.getClass().getDeclaredFields();
String str = "";
for (Field field : fields) {
// System.out.println(field.getName());
str += (":" + field.getName());
}
fields = bean.getClass().getSuperclass().getDeclaredFields();
for (Field field : fields) {
// System.out.println(field.getName());
str += (":" + field.getName());
}
str += ":";
for (String s : _nory_changes) {
str = str.replace(":" + s + ":", ":");
}
json = JSONObject.fromObject(bean, configJson(str.split(":")));

} else {// 转换除了_nory_changes里的属性
json = JSONObject.fromObject(bean, configJson(_nory_changes));
}
return json.toString();
}

private static JsonConfig configJson(String[] excludes) {

JsonConfig jsonConfig = new JsonConfig();

jsonConfig.setExcludes(excludes);
// 去掉setIgnoreDefaultExcludes(true)的话,就只会输出name,不会输出class
jsonConfig.setIgnoreDefaultExcludes(false); // //默认为false
//
// jsonConfig.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT);
// jsonConfig.registerJsonValueProcessor(Date.class,
//
// new DateJsonValueProcessor(datePattern));
return jsonConfig;
}

/**
* 将java对象List集合转换成json字符串
*
* @param beans
* @return
*/
@SuppressWarnings("unchecked")
public static String beanListToJson(List beans) {
StringBuffer rest = new StringBuffer();
rest.append("[");
int size = beans.size();
for (int i = 0; i < size; i++) {
rest.append(beanToJson(beans.get(i)) + ((i < size - 1) ? "," : ""));
}
rest.append("]");
return rest.toString();
}

/**
*
* @param beans
* @param _no_changes
* @return
*/
@SuppressWarnings("unchecked")
public static String beanListToJson(List beans, String[] _nory_changes,
boolean nory) {
StringBuffer rest = new StringBuffer();
rest.append("[");
int size = beans.size();
for (int i = 0; i < size; i++) {
try {
rest.append(beanToJson(beans.get(i), _nory_changes, nory));
if (i < size - 1) {
rest.append(",");
}
} catch (Exception e) {
e.printStackTrace();
}
}
rest.append("]");
return rest.toString();
}

/**
* 从json字符串，获得HashMap数据 从json HASH表达式中获取一个map，改map支持嵌套功能
*
* @param jsonString
* @return
*/
@SuppressWarnings({ "unchecked" })
public static Map jsonToMap(String jsonString) {

JSONObject jsonObject = JSONObject.fromObject(jsonString);
Iterator keyIter = jsonObject.keys();
String key;
Object value;
Map valueMap = new HashMap();
while (keyIter.hasNext()) {
key = (String) keyIter.next();
value = jsonObject.get(key).toString();
valueMap.put(key, value);
}
return valueMap;
}

/**
* map集合转换成json格式数据
*
* @param map
* @return
*/
public static String mapToJson(Map<String, ?> map, String[] _nory_changes,
boolean nory) {
String s_json = "{";
Set<String> key = map.keySet();
for (Iterator<?> it = key.iterator(); it.hasNext();) {
String s = (String) it.next();
if (map.get(s) == null) {

} else if (map.get(s) instanceof List<?>) {
s_json += (s + ":" + JsonPluginsUtil.beanListToJson(
(List<?>) map.get(s), _nory_changes, nory));

} else {
JSONObject json = JSONObject.fromObject(map);
s_json += (s + ":" + json.toString());
}
if (it.hasNext()) {
s_json += ",";
}
}

s_json += "}";
return s_json;
}

/**
* 从json数组中得到相应java数组
*
* @param jsonString
* @return
*/
public static Object[] jsonToObjectArray(String jsonString) {
JSONArray jsonArray = JSONArray.fromObject(jsonString);
return jsonArray.toArray();
}

public static String listToJson(List<?> list) {
JSONArray jsonArray = JSONArray.fromObject(list);
return jsonArray.toString();
}

/**
* 从json对象集合表达式中得到一个java对象列表
*
* @param jsonString
* @param beanClass
* @return
*/
@SuppressWarnings("unchecked")
public static <T> List<T> jsonToBeanList(String jsonString,
Class<T> beanClass) {

JSONArray jsonArray = JSONArray.fromObject(jsonString);
JSONObject jsonObject;
T bean;
int size = jsonArray.size();
List<T> list = new ArrayList<T>(size);

for (int i = 0; i < size; i++) {
jsonObject = jsonArray.getJSONObject(i);
bean = (T) JSONObject.toBean(jsonObject, beanClass);
list.add(bean);
}
return list;
}

/**
* 从json数组中解析出java字符串数组
*
* @param jsonString
* @return
*/
public static String[] jsonToStringArray(String jsonString) {

JSONArray jsonArray = JSONArray.fromObject(jsonString);
String[] stringArray = new String[jsonArray.size()];
int size = jsonArray.size();
for (int i = 0; i < size; i++) {
stringArray[i] = jsonArray.getString(i);
}
return stringArray;
}

/**
* 从json数组中解析出javaLong型对象数组
*
* @param jsonString
* @return
*/
public static Long[] jsonToLongArray(String jsonString) {

JSONArray jsonArray = JSONArray.fromObject(jsonString);
int size = jsonArray.size();
Long[] longArray = new Long[size];
for (int i = 0; i < size; i++) {
longArray[i] = jsonArray.getLong(i);
}
return longArray;
}

/**
* 从json数组中解析出java Integer型对象数组
*
* @param jsonString
* @return
*/
public static Integer[] jsonToIntegerArray(String jsonString) {

JSONArray jsonArray = JSONArray.fromObject(jsonString);
int size = jsonArray.size();
Integer[] integerArray = new Integer[size];
for (int i = 0; i < size; i++) {
integerArray[i] = jsonArray.getInt(i);
}
return integerArray;
}

/**
* 从json数组中解析出java Double型对象数组
*
* @param jsonString
* @return
*/
public static Double[] jsonToDoubleArray(String jsonString) {

JSONArray jsonArray = JSONArray.fromObject(jsonString);
int size = jsonArray.size();
Double[] doubleArray = new Double[size];
for (int i = 0; i < size; i++) {
doubleArray[i] = jsonArray.getDouble(i);
}
return doubleArray;
}

// ////////////////////////////////////////自定义工具类////////////////////////////////////////////////

/*
* @Test public void testBeanToJsonStr(){ User user = new
* User("chenrongdong",18,new Date(),null); String [] strs= {"name","user"};
* System.out.println(beanToJsonStr(user,strs,null)); }
*/

/**
* 将java对象转换成json字符串
*
* @param excludes
* 不需要转换的属性
* @param flag
* 是否排除指定的属性，默认为ture
*/
public static String beanToJsonStr(Object bean, String[] excludes,
Boolean flag) {
JSONArray obj = JSONArray.fromObject(bean, configJson(excludes, flag));
return obj.toString();
}

private static JsonConfig configJson(String[] excludes, Boolean flag) {
if (flag == null) {
flag = true;
}
JsonConfig config = new JsonConfig();

config.registerJsonValueProcessor(Date.class, new JsonValueProcessor() {
private SimpleDateFormat sdf = new SimpleDateFormat(
"yyyy-MM-dd HH:mm:ss");

public Object processArrayValue(Object value, JsonConfig config) {
return this.process(value);
}

public Object processObjectValue(String key, Object value, JsonConfig config) {
return this.process(value);
}

private Object process(Object val) {
if (val == null) {
return "";
} else if (val instanceof Date)
return sdf.format((Date) val);
else {
return val.toString();
}
}
});

if (flag) {
config.setExcludes(excludes);
}
// 去掉setIgnoreDefaultExcludes(true)的话,就只会输出name,不会输出class
config.setIgnoreDefaultExcludes(false); // 默认为false
// 当类在当前文件夹下时，要防止自循环，需要配置jsonConfig
config.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT);

return config;

}
}