java and json interchangeable (settlement date of issue)

Aug 31 posted in Java (RSS), comments.

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JSON or JavaScript Object Natation, it is a lightweight data interchange format, is ideal for server and JavaScript interaction. In this paper, to explain under the conversion between java and JSON, in particular, to address each question of the date of conversion experience.
One needs the relevant jar package:
json-lib-xxx.jar
ezmorph-xxx.jar
commons-httpclient-xxx.jar
commons-lang-xxx.jar
commons-logging-xxx.jar
commons-collections-xxx.jar
The above packages can be downloaded from the following link:
http://commons.apache.org/index.html
http://json-lib.sourceforge.net
http://ezmorph.sourceforge.net
2, java-"JSON
1.List-"JSON

List<String> list = new ArrayList<String>();
        list.add("apple");
        list.add("orange");
        JSONArray jarr = JSONArray.fromObject(list);
        System.out.println("list->json:" + jarr.toString());

Print Results: list-> json: [ "apple", "orange"]
2.Map-"JSON

Map<String, Object> map = new HashMap<String, Object>();
        map.put("name", "Michael");
        map.put("baby", new String[] { "Lucy", "Lily" });
        map.put("age", 30);
        JSONObject jo = JSONObject.fromObject(map);
        System.out.println("map->json:" + jo.toString());

Print Results: map-> json: ( "age": 30, "name": "Michael", "baby": [ "Lucy", "Lily"])
3.bean-> JSON

JsonBean bean = new JsonBean();
        bean.setName("NewBaby");
        bean.setAge(1);
        bean.setBorn(new Date());
        jo = JSONObject.fromObject(bean);
        System.out.println("bean->json:" + jo.toString());

Print Results: bean-> json: ( "age": 1, "born": ( "date": 10, "day": 3, "hours": 14, "minutes": 14, "month": 2, "seconds": 1, "time": 1268201641228, "timezoneOffset": -480, "year": 110), "name": "NewBaby")
Then you will find it inside the bean object util.Date all of the attributes of this type of conversion out of 11. In actual application process, in most cases we hope to translate into yyyy-MM-dd format, Here's to talk about how to achieve:
First, write a new class JsonDateValueProcessor are as follows:

/**
 * JSON  Date formats to handle  (java Into  JSON)
 * @author Michael sun
 */
public class JsonDateValueProcessor implements JsonValueProcessor {

    /**
     * datePattern
     */
    private String datePattern = "yyyy-MM-dd";

    /**
     * JsonDateValueProcessor
     */
    public JsonDateValueProcessor() {
        super();
    }

    /**
     * @param format
     */
    public JsonDateValueProcessor(String format) {
        super();
        this.datePattern = format;
    }

    /**
     * @param value
     * @param jsonConfig
     * @return Object
     */
    public Object processArrayValue(Object value, JsonConfig jsonConfig) {
        return process(value);
    }

    /**
     * @param key
     * @param value
     * @param jsonConfig
     * @return Object
     */
    public Object processObjectValue(String key, Object value,
            JsonConfig jsonConfig) {
        return process(value);
    }

    /**
     * process
     * @param value
     * @return
     */
    private Object process(Object value) {
        try {
            if (value instanceof Date) {
                SimpleDateFormat sdf = new SimpleDateFormat(datePattern,
                        Locale.UK);
                return sdf.format((Date) value);
            }
            return value == null ? "" : value.toString();
        } catch (Exception e) {
            return "";
        }

    }

    /**
     * @return the datePattern
     */
    public String getDatePattern() {
        return datePattern;
    }

    /**
     * @param pDatePattern the datePattern to set
     */
    public void setDatePattern(String pDatePattern) {
        datePattern = pDatePattern;
    }

}

Test Code:

JsonBean bean = new JsonBean();
        bean.setName("NewBaby");
        bean.setAge(1);
        bean.setBorn(new Date());

        JsonConfig jsonConfig = new JsonConfig();
        jsonConfig.registerJsonValueProcessor(Date.class,
                new JsonDateValueProcessor());

        JSONObject jo = JSONObject.fromObject(bean, jsonConfig);
        System.out.println("bean->json:" + jo.toString());

Print Results: bean-> json: ( "age": 1, "born": "2010-03-10", "name": "NewBaby")
It can get what we want result.

3, JSON-"java
1. How to json in yyyy-MM-dd conversion of the Bean in the util.Date type:

JSONUtils.getMorpherRegistry().registerMorpher(
                new DateMorpher(new String[] { "yyyy-MM-dd" }));

        String jsonStr = "[{\"name\": \"husband\", \"age\": \"26\", \"born\": \"1984-01-12\"},{\"name\": \"wife\", \"age\": \"20\", \"born\": \"1990-05-01\"}]";

        Collection<JsonBean> list = JSONArray.toCollection(JSONArray
                .fromObject(jsonStr), JsonBean.class);
      //DateUtil.getFormatDate(date,fmtstr) Date change string here no longer write code  
        for (JsonBean o : list) {
            System.out.println(DateUtil
                    .getFormatDate(o.getBorn(), "yyyy-MM-dd"));
        }

Print Results:
1984-01-12
1990-05-01
2. JSON-"List, Map

String listStr = "[\"apple\",\"orange\"]";
        Collection<String> strlist = JSONArray.toCollection(JSONArray
                .fromObject(listStr));
        for (String str : strlist) {
            System.out.println(str);
        }

        String mapStr = "{\"age\":30,\"name\":\"Michael\",\"baby\":[\"Lucy\",\"Lily\"]}";
        Map<String, Object> map = (Map) JSONObject.toBean(JSONObject
                .fromObject(mapStr), Map.class);
        for (Entry<String, Object> entry : map.entrySet()) {
            System.out.println(entry.getKey() + "  " + entry.getValue());
        }

Print Results:
apple
orange
name Michael
age 30
baby [Lucy, Lily]