Java操作JSON数据(1)--JSON-lib操作JSON数据

JSON-lib是一个java库，用于将bean、映射、集合、java数组和XML转换为JSON，或将JSON转为beans和DynaBeans。JSON-lib最后的版本是2.4，更新时间是2010年12月14日，在以前的项目或系统中用的用的较多；本文简单介绍下其使用方法。文中所使用到的软件版本：Java 1.8.0_191、JSON-lib 2.4。

1、引入依赖

        <dependency>
            <groupId>net.sf.json-lib</groupId>
            <artifactId>json-lib</artifactId>
            <version>2.4</version>
            <classifier>jdk15</classifier>
        </dependency>

2、序列化

    public static String serialize() {
        MyBean bean = new MyBean();
        bean.setS("测试字符串");
        Calendar calendar = Calendar.getInstance();
        calendar.add(Calendar.HOUR_OF_DAY, -1);
        bean.setD(calendar.getTime());
        JsonConfig config = new JsonConfig();
        //防止自包含
        config.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT);
        //Date类型转化
        config.registerJsonValueProcessor(Date.class, new DateJsonValueProcessor());
        //过滤s3字段
        config.setExcludes(new String[]{"s3"});
        //过滤值为null的字段
        config.setJsonPropertyFilter(new PropertyFilter() {
            @Override
            public boolean apply(Object arg0, String arg1, Object value) {
                return value == null;
            }
        });
        List<MyBean> list = new ArrayList<MyBean>();
        list.add(bean);
        Map<String, List<MyBean>> map = new HashMap<String, List<MyBean>>();
        map.put("data", list);
        JSON json = JSONSerializer.toJSON(map, config);
        String result = json.toString();
        System.out.println(json.toString());
        return result;
    }

3、反序列化

    public static void deserialize() {
        try {
            //处理日期类型
            JSONUtils.getMorpherRegistry().registerMorpher(new DateMorpher(new String[]{"yyyy-MM-dd HH:mm:ss"}));
            String s = serialize();
            Map<String, Class<?>> classMap = new HashMap<String, Class<?>>();  
            classMap.put("data", MyBean.class);
            Map<String, List<MyBean>> map = (Map<String, List<MyBean>>) JSONObject.toBean(JSONObject.fromObject(s), Map.class, classMap);
            System.out.println(map);
            
            //直接通过api获取相应数据
            JSONObject obj = JSONObject.fromObject(s);
            JSONArray data = obj.getJSONArray("data");
            JSONObject bean = data.getJSONObject(0);
            System.out.println(bean.getString("s"));
            //...
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

4、完整例子

package com.inspur.demo.json;

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import net.sf.ezmorph.object.DateMorpher;
import net.sf.json.JSON;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import net.sf.json.JSONSerializer;
import net.sf.json.JsonConfig;
import net.sf.json.processors.JsonValueProcessor;
import net.sf.json.util.CycleDetectionStrategy;
import net.sf.json.util.JSONUtils;
import net.sf.json.util.PropertyFilter;

/**
 * JSON-lib操作JSON数据
 */
public class JsonLibCase {
    /**
     * 序列化
     */
    public static String serialize() {
        MyBean bean = new MyBean();
        bean.setS("测试字符串");
        Calendar calendar = Calendar.getInstance();
        calendar.add(Calendar.HOUR_OF_DAY, -1);
        bean.setD(calendar.getTime());
        JsonConfig config = new JsonConfig();
        //防止自包含
        config.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT);
        //Date类型转化
        config.registerJsonValueProcessor(Date.class, new DateJsonValueProcessor());
        //过滤s3字段
        config.setExcludes(new String[]{"s3"});
        //过滤值为null的字段
        config.setJsonPropertyFilter(new PropertyFilter() {
            @Override
            public boolean apply(Object arg0, String arg1, Object value) {
                return value == null;
            }
        });
        List<MyBean> list = new ArrayList<MyBean>();
        list.add(bean);
        Map<String, List<MyBean>> map = new HashMap<String, List<MyBean>>();
        map.put("data", list);
        JSON json = JSONSerializer.toJSON(map, config);
        String result = json.toString();
        System.out.println(json.toString());
        return result;
    }
    
    /**
     * 反序列化
     */
    public static void deserialize() {
        try {
            //处理日期类型
            JSONUtils.getMorpherRegistry().registerMorpher(new DateMorpher(new String[]{"yyyy-MM-dd HH:mm:ss"}));
            String s = serialize();
            Map<String, Class<?>> classMap = new HashMap<String, Class<?>>();  
            classMap.put("data", MyBean.class);
            Map<String, List<MyBean>> map = (Map<String, List<MyBean>>) JSONObject.toBean(JSONObject.fromObject(s), Map.class, classMap);
            System.out.println(map);
            
            //直接通过api获取相应数据
            JSONObject obj = JSONObject.fromObject(s);
            JSONArray data = obj.getJSONArray("data");
            JSONObject bean = data.getJSONObject(0);
            System.out.println(bean.getString("s"));
            //...
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    
    public static void main(String[] args) {
        serialize();
        deserialize();
    }
    
    static class DateJsonValueProcessor implements JsonValueProcessor {
        @Override
        public Object processArrayValue(Object value, JsonConfig arg1) {
            return process(value);
        }

        @Override
        public Object processObjectValue(String key, Object value, JsonConfig arg2) {
            return process(value);
        }
        private Object process(Object value) {
            try {
                if (value instanceof Date) {
                    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
                    return sdf.format((Date) value);
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return value == null ? "" : value.toString();
        }
    }
}

package com.inspur.demo.json;

import java.util.Arrays;
import java.util.Date;

public class MyBean {
    private String s = "字符串";
    private String s2;
    private String s3 = "字符串3";
    private int i = 123;
    private Integer i2;
    private char c = '到';
    private char[] c2 = new char[]{'a', 'b'};
    private Date d = new Date();
    private Date[] d2 = new Date[]{new Date(), new Date()};
    public String getS() {
        return s;
    }
    public void setS(String s) {
        this.s = s;
    }
    public String getS2() {
        return s2;
    }
    public void setS2(String s2) {
        this.s2 = s2;
    }
    public String getS3() {
        return s3;
    }
    public void setS3(String s3) {
        this.s3 = s3;
    }
    public int getI() {
        return i;
    }
    public void setI(int i) {
        this.i = i;
    }
    public Integer getI2() {
        return i2;
    }
    public void setI2(Integer i2) {
        this.i2 = i2;
    }
    public char getC() {
        return c;
    }
    public void setC(char c) {
        this.c = c;
    }
    public char[] getC2() {
        return c2;
    }
    public void setC2(char[] c2) {
        this.c2 = c2;
    }
    public Date getD() {
        return d;
    }
    public void setD(Date d) {
        this.d = d;
    }
    public Date[] getD2() {
        return d2;
    }
    public void setD2(Date[] d2) {
        this.d2 = d2;
    }
    @Override
    public String toString() {
        return "MyBean [s=" + s + ", s2=" + s2 + ", s3=" + s3 + ", i=" + i + ", i2=" + i2 + ", c=" + c + ", c2="
                + Arrays.toString(c2) + ", d=" + d + ", d2=" + Arrays.toString(d2) + "]";
    }
}