ANDROID轻量级JSON序列化和反序列化［转］

ANDROID JSON解析工具类，不需要第三方包，支持集合，直接贴代码。

 

import java.lang.reflect.Array;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Set;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONStringer;

import android.util.Log;


/**
 * @author keane
 * @version 1.0
 *
 */
public class JSONHelper {

    private static String TAG = "JSONHelper";

    /**
     * 将对象转换成Json字符串
     * @param obj
     * @return
     */
    public static String toJSON(Object obj) {
        JSONStringer js = new JSONStringer();
        serialize(js, obj);
        return js.toString();
    }

    /**
     * 序列化为JSON
     * @param js
     * @param o
     */
    private static void serialize(JSONStringer js, Object o) {
        if (isNull(o)) {
            try {
                js.value(null);
            } catch (JSONException e) {
                e.printStackTrace();
            }
            return;
        }

        Class<?> clazz = o.getClass();
        if (isObject(clazz)) { // 对象
            serializeObject(js, o);
        } else if (isArray(clazz)) { // 数组
            serializeArray(js, o);
        } else if (isCollection(clazz)) { // 集合
            Collection<?> collection = (Collection<?>) o;
            serializeCollect(js, collection);
        } else { // 单个值
            try {
                js.value(o);
            } catch (JSONException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * 序列化数组
     * @param js
     * @param array
     */
    private static void serializeArray(JSONStringer js, Object array) {
        try {
            js.array();
            for (int i = 0; i < Array.getLength(array); ++i) {
                Object o = Array.get(array, i);
                serialize(js, o);
            }
            js.endArray();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 序列化集合
     * @param js
     * @param collection
     */
    private static void serializeCollect(JSONStringer js, Collection<?> collection) {
        try {
            js.array();
            for (Object o : collection) {
                serialize(js, o);
            }
            js.endArray();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 序列化对象
     * @param js
     * @param obj
     */
    private static void serializeObject(JSONStringer js, Object obj) {
        try {
            js.object();
            Class<? extends Object> objClazz = obj.getClass();
            Method[] methods = objClazz.getDeclaredMethods();
            Field[] fields = objClazz.getDeclaredFields();
            for (Field field : fields) {
                try {
                    String fieldType = field.getType().getSimpleName();
                    String fieldGetName = parseMethodName(field.getName(),"get");
                    if (!haveMethod(methods, fieldGetName)) {
                        continue;
                    }
                    Method fieldGetMet = objClazz.getMethod(fieldGetName, new Class[] {});
                    Object fieldVal = fieldGetMet.invoke(obj, new Object[] {});
                    String result = null;
                    if ("Date".equals(fieldType)) {
                        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss",
                                Locale.US);
                        result = sdf.format((Date)fieldVal);

                    } else {
                        if (null != fieldVal) {
                            result = String.valueOf(fieldVal);
                        }
                    }
                    js.key(field.getName());
                    serialize(js, result);
                } catch (Exception e) {
                    continue;
                }
            }
            js.endObject();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 判断是否存在某属性的 get方法
     *
     * @param methods
     * @param fieldGetMet
     * @return boolean
     */
    public static boolean haveMethod(Method[] methods, String fieldMethod) {
        for (Method met : methods) {
            if (fieldMethod.equals(met.getName())) {
                return true;
            }
        }
        return false;
    }

    /**
     * 拼接某属性的 get或者set方法
     * @param fieldName
     * @param methodType
     * @return
     */
    public static String parseMethodName(String fieldName,String methodType) {
        if (null == fieldName || "".equals(fieldName)) {
            return null;
        }
        return methodType + fieldName.substring(0, 1).toUpperCase()
                + fieldName.substring(1);
    }



    /**
     * set属性的值到Bean
     * @param obj
     * @param valMap
     */
    public static void setFieldValue(Object obj, Map<String, String> valMap) {
        Class<?> cls = obj.getClass();
        // 取出bean里的所有方法
        Method[] methods = cls.getDeclaredMethods();
        Field[] fields = cls.getDeclaredFields();

        for (Field field : fields) {
            try {
                String setMetodName = parseMethodName(field.getName(),"set");
                if (!haveMethod(methods, setMetodName)) {
                    continue;
                }
                Method fieldMethod = cls.getMethod(setMetodName, field
                        .getType());
                String value = valMap.get(field.getName());
                if (null != value && !"".equals(value)) {
                    String fieldType = field.getType().getSimpleName();
                    if ("String".equals(fieldType)) {
                        fieldMethod.invoke(obj, value);
                    } else if ("Date".equals(fieldType)) {
                        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss",Locale.US);
                        Date temp = sdf.parse(value);
                        fieldMethod.invoke(obj, temp);
                    } else if ("Integer".equals(fieldType)
                            || "int".equals(fieldType)) {
                        Integer intval = Integer.parseInt(value);
                        fieldMethod.invoke(obj, intval);
                    } else if ("Long".equalsIgnoreCase(fieldType)) {
                        Long temp = Long.parseLong(value);
                        fieldMethod.invoke(obj, temp);
                    } else if ("Double".equalsIgnoreCase(fieldType)) {
                        Double temp = Double.parseDouble(value);
                        fieldMethod.invoke(obj, temp);
                    } else if ("Boolean".equalsIgnoreCase(fieldType)) {
                        Boolean temp = Boolean.parseBoolean(value);
                        fieldMethod.invoke(obj, temp);
                    } else {
                        System.out.println("setFieldValue not supper type:" + fieldType);
                    }
                }
            } catch (Exception e) {
                continue;
            }
        }

    }

    /**
     * 对象转Map
     * @param obj
     * @return
     */
    public static Map<String, String> getFieldValueMap(Object obj) {
        Class<?> cls = obj.getClass();
        Map<String, String> valueMap = new HashMap<String, String>();
        // 取出bean里的所有方法
        Method[] methods = cls.getDeclaredMethods();
        Field[] fields = cls.getDeclaredFields();
        for (Field field : fields) {
            try {
                String fieldType = field.getType().getSimpleName();
                String fieldGetName = parseMethodName(field.getName(),"get");
                if (!haveMethod(methods, fieldGetName)) {
                    continue;
                }
                Method fieldGetMet = cls.getMethod(fieldGetName, new Class[] {});
                Object fieldVal = fieldGetMet.invoke(obj, new Object[] {});
                String result = null;
                if ("Date".equals(fieldType)) {
                    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss",Locale.CHINA);
                    result = sdf.format((Date)fieldVal);

                } else {
                    if (null != fieldVal) {
                        result = String.valueOf(fieldVal);
                    }
                }
                valueMap.put(field.getName(), result);
            } catch (Exception e) {
                continue;
            }
        }
        return valueMap;

    }



    /**
     * 给对象的字段赋值
     * @param obj
     * @param fieldSetMethod
     * @param fieldType
     * @param value
     */
    public static void setFiedlValue(Object obj,Method fieldSetMethod,String fieldType,Object value){

        try {
            if (null != value && !"".equals(value)) {
                if ("String".equals(fieldType)) {
                    fieldSetMethod.invoke(obj, value.toString());
                } else if ("Date".equals(fieldType)) {
                    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss",Locale.CHINA);
                    Date temp = sdf.parse(value.toString());
                    fieldSetMethod.invoke(obj, temp);
                } else if ("Integer".equals(fieldType)
                        || "int".equals(fieldType)) {
                    Integer intval = Integer.parseInt(value.toString());
                    fieldSetMethod.invoke(obj, intval);
                } else if ("Long".equalsIgnoreCase(fieldType)) {
                    Long temp = Long.parseLong(value.toString());
                    fieldSetMethod.invoke(obj, temp);
                } else if ("Double".equalsIgnoreCase(fieldType)) {
                    Double temp = Double.parseDouble(value.toString());
                    fieldSetMethod.invoke(obj, temp);
                } else if ("Boolean".equalsIgnoreCase(fieldType)) {
                    Boolean temp = Boolean.parseBoolean(value.toString());
                    fieldSetMethod.invoke(obj, temp);
                } else {
                    fieldSetMethod.invoke(obj, value);
                    Log.e(TAG, TAG  + ">>>>setFiedlValue -> not supper type" + fieldType);
                }
            }

        } catch (Exception e) {
            Log.e(TAG, TAG  + ">>>>>>>>>>set value error.",e);
        }

    }


    /**
     * 反序列化简单对象
     * @param jo
     * @param clazz
     * @return
     * @throws JSONException
     */
    public static <T> T parseObject(JSONObject jo, Class<T> clazz) throws JSONException {
        if (clazz == null || isNull(jo)) {
            return null;
        }

        T obj = newInstance(clazz);
        if (obj == null) {
            return null;
        }
        if(isMap(clazz)){
            setField(obj,jo);
        }else{
              // 取出bean里的所有方法
            Method[] methods = clazz.getDeclaredMethods();
            Field[] fields = clazz.getDeclaredFields();
            for (Field f : fields) {
                String setMetodName = parseMethodName(f.getName(),"set");
                if (!haveMethod(methods, setMetodName)) {
                    continue;
                }
                try {
                    Method fieldMethod = clazz.getMethod(setMetodName, f.getType());
                    setField(obj,fieldMethod,f, jo);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
        return obj;
    }


    /**
     * 反序列化简单对象
     * @param jsonString
     * @param clazz
     * @return
     * @throws JSONException
     */
    public static <T> T parseObject(String jsonString, Class<T> clazz) throws JSONException {
        if (clazz == null || jsonString == null || jsonString.length() == 0) {
            return null;
        }

        JSONObject jo = null;
        jo = new JSONObject(jsonString);
        if (isNull(jo)) {
            return null;
        }

        return parseObject(jo, clazz);
    }

    /**
     * 反序列化数组对象
     * @param ja
     * @param clazz
     * @return
     */
    public static <T> T[] parseArray(JSONArray ja, Class<T> clazz) {
        if (clazz == null || isNull(ja)) {
            return null;
        }

        int len = ja.length();

        @SuppressWarnings("unchecked")
        T[] array = (T[]) Array.newInstance(clazz, len);

        for (int i = 0; i < len; ++i) {
            try {
                JSONObject jo = ja.getJSONObject(i);
                T o = parseObject(jo, clazz);
                array[i] = o;
            } catch (JSONException e) {
                e.printStackTrace();
            }
        }

        return array;
    }


    /**
     * 反序列化数组对象
     * @param jsonString
     * @param clazz
     * @return
     */
    public static <T> T[] parseArray(String jsonString, Class<T> clazz) {
        if (clazz == null || jsonString == null || jsonString.length() == 0) {
            return null;
        }
        JSONArray jo = null;
        try {
            jo = new JSONArray(jsonString);
        } catch (JSONException e) {
            e.printStackTrace();
        }

        if (isNull(jo)) {
            return null;
        }

        return parseArray(jo, clazz);
    }

    /**
     * 反序列化泛型集合
     * @param ja
     * @param collectionClazz
     * @param genericType
     * @return
     * @throws JSONException
     */
    @SuppressWarnings("unchecked")
    public static <T> Collection<T> parseCollection(JSONArray ja, Class<?> collectionClazz,
            Class<T> genericType) throws JSONException {

        if (collectionClazz == null || genericType == null || isNull(ja)) {
            return null;
        }

        Collection<T> collection = (Collection<T>) newInstance(collectionClazz);

        for (int i = 0; i < ja.length(); ++i) {
            try {
                JSONObject jo = ja.getJSONObject(i);
                T o = parseObject(jo, genericType);
                collection.add(o);
            } catch (JSONException e) {
                e.printStackTrace();
            }
        }

        return collection;
    }

    /**
     * 反序列化泛型集合
     * @param jsonString
     * @param collectionClazz
     * @param genericType
     * @return
     * @throws JSONException
     */
    public static <T> Collection<T> parseCollection(String jsonString, Class<?> collectionClazz,
            Class<T> genericType) throws JSONException {
        if (collectionClazz == null || genericType == null || jsonString == null
                || jsonString.length() == 0) {
            return null;
        }
        JSONArray jo = null;
        try {
            jo = new JSONArray(jsonString);
        } catch (JSONException e) {
            e.printStackTrace();
        }

        if (isNull(jo)) {
            return null;
        }

        return parseCollection(jo, collectionClazz, genericType);
    }

    /**
     * 根据类型创建对象
     * @param clazz
     * @return
     * @throws JSONException
     */
    private static <T> T newInstance(Class<T> clazz) throws JSONException {
        if (clazz == null)
            return null;
        T obj = null;
        if (clazz.isInterface()) {
            if (clazz.equals(Map.class)) {
                obj = (T) new HashMap();
            }else if (clazz.equals(List.class)) {
                obj = (T) new ArrayList();
            }else if (clazz.equals(Set.class)) {
                obj = (T) new HashSet();
            }else{
                throw new JSONException("unknown interface: " + clazz);
            }
        }else{
            try {
                obj = clazz.newInstance();
            }catch (Exception e) {
                throw new JSONException("unknown class type: " + clazz);
            }
        }
        return obj;
    }

    /**
     * 设定Map的值
     * @param obj
     * @param jo
     */
    private static void setField(Object obj, JSONObject jo) {
        try {
            @SuppressWarnings("unchecked")
            Iterator<String> keyIter = jo.keys();
            String key;
            Object value;
            @SuppressWarnings("unchecked")
            Map<String, Object> valueMap = (Map<String, Object>) obj;
            while (keyIter.hasNext()) {
                key = (String) keyIter.next();
                value = jo.get(key);
                valueMap.put(key, value);

            }
        } catch (JSONException e) {
            e.printStackTrace();
        }
    }


    /**
     * 设定字段的值
     * @param obj
     * @param fieldSetMethod
     * @param f
     * @param jo
     */
    private static void setField(Object obj, Method fieldSetMethod,Field f, JSONObject jo) {
        String name = f.getName();
        Class<?> clazz = f.getType();
        try {
            if (isArray(clazz)) { // 数组
                Class<?> c = clazz.getComponentType();
                JSONArray ja = jo.optJSONArray(name);
                if (!isNull(ja)) {
                    Object array = parseArray(ja, c);
                    setFiedlValue(obj, fieldSetMethod, clazz.getSimpleName(), array);
                }
            } else if (isCollection(clazz)) { // 泛型集合
                // 获取定义的泛型类型
                Class<?> c = null;
                Type gType = f.getGenericType();
                if (gType instanceof ParameterizedType) {
                    ParameterizedType ptype = (ParameterizedType) gType;
                    Type[] targs = ptype.getActualTypeArguments();
                    if (targs != null && targs.length > 0) {
                        Type t = targs[0];
                        c = (Class<?>) t;
                    }
                }

                JSONArray ja = jo.optJSONArray(name);
                if (!isNull(ja)) {
                    Object o = parseCollection(ja, clazz, c);
                    setFiedlValue(obj, fieldSetMethod, clazz.getSimpleName(), o);
                }
            } else if (isSingle(clazz)) { // 值类型
                Object o = jo.opt(name);
                if (o != null) {
                    setFiedlValue(obj, fieldSetMethod, clazz.getSimpleName(), o);
                }
            } else if (isObject(clazz)) { // 对象
                JSONObject j = jo.optJSONObject(name);
                if (!isNull(j)) {
                    Object o = parseObject(j, clazz);
                    setFiedlValue(obj, fieldSetMethod, clazz.getSimpleName(), o);
                }
            } else if (isList(clazz)) { // 列表
//              JSONObject j = jo.optJSONObject(name);
//              if (!isNull(j)) {
//                  Object o = parseObject(j, clazz);
//                  f.set(obj, o);
//              }
            } else {
                throw new Exception("unknow type!");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 设定字段的值
     * @param obj
     * @param f
     * @param jo
     */
    private static void setField(Object obj, Field f, JSONObject jo) {
        String name = f.getName();
        Class<?> clazz = f.getType();
        try {
            if (isArray(clazz)) { // 数组
                Class<?> c = clazz.getComponentType();
                JSONArray ja = jo.optJSONArray(name);
                if (!isNull(ja)) {
                    Object array = parseArray(ja, c);
                    f.set(obj, array);
                }
            } else if (isCollection(clazz)) { // 泛型集合
                // 获取定义的泛型类型
                Class<?> c = null;
                Type gType = f.getGenericType();
                if (gType instanceof ParameterizedType) {
                    ParameterizedType ptype = (ParameterizedType) gType;
                    Type[] targs = ptype.getActualTypeArguments();
                    if (targs != null && targs.length > 0) {
                        Type t = targs[0];
                        c = (Class<?>) t;
                    }
                }

                JSONArray ja = jo.optJSONArray(name);
                if (!isNull(ja)) {
                    Object o = parseCollection(ja, clazz, c);
                    f.set(obj, o);
                }
            } else if (isSingle(clazz)) { // 值类型
                Object o = jo.opt(name);
                if (o != null) {
                    f.set(obj, o);
                }
            } else if (isObject(clazz)) { // 对象
                JSONObject j = jo.optJSONObject(name);
                if (!isNull(j)) {
                    Object o = parseObject(j, clazz);
                    f.set(obj, o);
                }
            } else if (isList(clazz)) { // 列表
                JSONObject j = jo.optJSONObject(name);
                if (!isNull(j)) {
                    Object o = parseObject(j, clazz);
                    f.set(obj, o);
                }
            }else {
                throw new Exception("unknow type!");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 判断对象是否为空
     * @param obj
     * @return
     */
    private static boolean isNull(Object obj) {
        if (obj instanceof JSONObject) {
            return JSONObject.NULL.equals(obj);
        }
        return obj == null;
    }

    /**
     * 判断是否是值类型
     * @param clazz
     * @return
     */
    private static boolean isSingle(Class<?> clazz) {
        return isBoolean(clazz) || isNumber(clazz) || isString(clazz);
    }

    /**
     * 是否布尔值
     * @param clazz
     * @return
     */
    public static boolean isBoolean(Class<?> clazz) {
        return (clazz != null)
                && ((Boolean.TYPE.isAssignableFrom(clazz)) || (Boolean.class
                        .isAssignableFrom(clazz)));
    }

    /**
     * 是否数值
     * @param clazz
     * @return
     */
    public static boolean isNumber(Class<?> clazz) {
        return (clazz != null)
                && ((Byte.TYPE.isAssignableFrom(clazz)) || (Short.TYPE.isAssignableFrom(clazz))
                        || (Integer.TYPE.isAssignableFrom(clazz))
                        || (Long.TYPE.isAssignableFrom(clazz))
                        || (Float.TYPE.isAssignableFrom(clazz))
                        || (Double.TYPE.isAssignableFrom(clazz)) || (Number.class
                        .isAssignableFrom(clazz)));
    }

    /**
     * 判断是否是字符串
     * @param clazz
     * @return
     */
    public static boolean isString(Class<?> clazz) {
        return (clazz != null)
                && ((String.class.isAssignableFrom(clazz))
                        || (Character.TYPE.isAssignableFrom(clazz)) || (Character.class
                        .isAssignableFrom(clazz)));
    }

    /**
     * 判断是否是对象
     * @param clazz
     * @return
     */
    private static boolean isObject(Class<?> clazz) {
        return clazz != null && !isSingle(clazz) && !isArray(clazz) && !isCollection(clazz);
    }

    /**
     * 判断是否是数组
     * @param clazz
     * @return
     */
    public static boolean isArray(Class<?> clazz) {
        return clazz != null && clazz.isArray();
    }

    /**
     * 判断是否是集合
     * @param clazz
     * @return
     */
    public static boolean isCollection(Class<?> clazz) {
        return clazz != null && Collection.class.isAssignableFrom(clazz);
    }

    /**
     * 判断是否是Map
     * @param clazz
     * @return
     */
    public static boolean isMap(Class<?> clazz) {
        return clazz != null && Map.class.isAssignableFrom(clazz);
    }

    /**
     * 判断是否是列表
     * @param clazz
     * @return
     */
    public static boolean isList(Class<?> clazz) {
        return clazz != null && List.class.isAssignableFrom(clazz);
    }

}

 

 

调用测试代码：

 

public class User{
    private String name;
    private String password;
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }

}

void testObj(){
    try {
        User user = new User();
        user.setName("abcd");
        user.setPassword("123456");

        User user1 = new User();
        user.setName("abcdf");
        user.setPassword("1234567");

        String jsonStrUser = JSONHelper.toJSON(user);   //序列化
        User jsonUser = JSONHelper.parseObject(jsonStrUser, User.class);    //反序列化
        Map mapUser = JSONHelper.parseObject(jsonStrUser, HashMap.class);   //反序列化


        List sourceList = new ArrayList<User>();
        sourceList.add(user);
        sourceList.add(user1);
        String jsonStrUserList = JSONHelper.toJSON(sourceList);         //序列化
        List listUser = (List) JSONHelper.parseCollection(jsonStrUserList, List.class, User.class); //反序列化
    } catch (JSONException e) {
        e.printStackTrace();
    }

}

 

评论

1 楼 landerson 2015-02-12  

明显就有要求的嘛