JSON conversion tool class

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.*;
import org.apache.commons.lang3.StringUtils;
import java.text.SimpleDateFormat;
import java.util.HashMap;
import java.util.Map;

/**
 * 
 * ClassName: JsonUtils.java <br>
 * Description:json  Tool class  <br>
 * Create by: name：luyong <br>email: [e-mail]
 */
public class JsonUtils {
    
    /**
     *  Default date format 
     */
    private static final String DATE_PATTERN = "yyyy-MM-dd HH:mm:ss";

    private static ObjectMapper defaultObjectMapper = getObjectMapper(null);

    /**
     *  Return to one Object object 
     * @param datePattern, Specify the date string format that can be processed , If not specified, the default is yyyy-MM-dd HH:mm:ss
     * @return
     */
    public static ObjectMapper getObjectMapper(String datePattern) {
    
        if (StringUtils.isBlank(datePattern)) {
    
            datePattern = DATE_PATTERN;
        }
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.setDateFormat(new SimpleDateFormat(datePattern));
        // Allow field names not to use quotation marks 
        objectMapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
        objectMapper.configure(JsonParser.Feature.ALLOW_UNQUOTED_CONTROL_CHARS, true);
        // Single quotation marks are allowed 
        objectMapper.configure(JsonParser.Feature.ALLOW_SINGLE_QUOTES, true);
        //  Ignore unrecognized parameters ( solve json Multi attribute in string , And undefined in the class )
        objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
        // Converts an object to string when ,json Of key Whether according to the object field The natural order of 
        objectMapper.configure(SerializationFeature.ORDER_MAP_ENTRIES_BY_KEYS, false);
        return objectMapper;
    }

    /**
     *  Convert the specified object to json character string . Date type according to  yyyy-MM-dd HH:mm:ss  Convert the format of to string 
     * @param obj  object 
     * @return json character string 
     */
    public static String writeValueAsString(Object obj){
    
        try {
    
            return getObjectMapper(null).writeValueAsString(obj);
        } catch (Exception e) {
    
            throw new RuntimeException(e);
        }
    }

    /**
     *  Convert the specified object to json character string 
     * @param object
     * @param datePattern  Specify the converted date format 
     * @return
     */
    public static String writeValueAsString(Object object, String datePattern) {
    
        try {
    
            return getObjectMapper(datePattern).writeValueAsString(object);
        } catch (Exception e) {
    
            throw new RuntimeException(e);
        }
    }

    /**
     *  Convert the specified object to json character string 
     * @param object
     * @param datePattern  Specify the converted date format 
     * @param indentOutput  Indent output 
     * @return
     */
    public static String writeValueAsString(Object object, String datePattern,boolean indentOutput) {
    
        try {
    
            ObjectMapper objectMapper = getObjectMapper(datePattern);
            objectMapper.configure(SerializationFeature.INDENT_OUTPUT, true);
            return objectMapper.writeValueAsString(object);
        } catch (Exception e) {
    
            throw new RuntimeException(e);
        }

    }

    /**
     *  take json String to object 
     * @param <T>  Return type 
     * @param content json character string 
     * @param valueType  Return type 
     * @return  object 
     */
    public static <T> T readValue(String content, Class<T> valueType) {
    
        try {
    
            ObjectMapper objectMapper = getObjectMapper(null);
            return objectMapper.readValue(content, valueType);
        } catch (Exception e) {
    
            throw new RuntimeException(e);
        }
    }

    /**
     *  take json Convert to object 
     * @param content
     * @param valueTypeRef
     * @return
     */
    public static <T> T readValue(String content, TypeReference<T> valueTypeRef){
    
        try {
    
            ObjectMapper objectMapper = getObjectMapper(null);
            return objectMapper.readValue(content, valueTypeRef);
        } catch (Exception e) {
    
            throw new RuntimeException(e);
        }
    }

    /**
     *  take json Convert to object 
     * @param content
     * @param valueTypeRef
     * @param dateStyle
     * @return
     */
    public static <T> T readValue(String content, TypeReference<T> valueTypeRef, String dateStyle){
    
        try {
    
            ObjectMapper objectMapper = getObjectMapper(dateStyle);
            return objectMapper.readValue(content, valueTypeRef);
        } catch (Exception e) {
    
            throw new RuntimeException(e);
        }
    }

    /**
     *  take json String to object , The date type is converted according to the given style 
     *
     * @param <T>  Return type 
     * @param content json character string 
     * @param valueType  Return type 
     * @param dateStyle  Date format 
     * @return  object 
     */
    public static <T> T readValue(String content, Class<T> valueType, String dateStyle) {
    
        try {
    
            ObjectMapper objectMapper = getObjectMapper(dateStyle);
            return objectMapper.readValue(content, valueType);
        } catch (Exception e) {
    
            throw new RuntimeException(e);
        }
    }

    /**
     *  According to what is given json String conversion  JsonNode  object 
     * @param content
     * @return
     */
    public static JsonNode readTree(String content){
    
        try {
    
            ObjectMapper objectMapper = getObjectMapper(null);
            return objectMapper.readTree(content);
        }catch (Exception e) {
    
            throw new RuntimeException(e);
        }

    }

    /**
     *  According to the given path , Return the corresponding  JsonNode object 
     * @param jsonNode
     * @param path  Path expression .  for example ： about {
    param:{
    transCode:"123"}}  Medium transCode It can be expressed as ,getJsonNode(jsonNode,"param.transCode")
     * @return
     */
    public static JsonNode getJsonNode(JsonNode jsonNode , String path){
    
        String[] pathArr = path.split("\\.");
        JsonNode temp = jsonNode;
        for(String filed : pathArr){
    
            temp = temp.get(filed);
        }
        return temp;
    }

    /**
     *  According to the given path , Return the corresponding  JsonNode object 
     * @param json
     * @param path
     * @return
     */
    public static JsonNode getJsonNode(String json , String path){
    
        JsonNode root = readTree(json);
        return getJsonNode(root,path);
    }

    /**
     *  Get the value of the given attribute 
     * @param jsonNode
     * @param path
     * @return
     */
    public static String getFieldValue(JsonNode jsonNode,String path){
    
        JsonNode node = getJsonNode(jsonNode,path);
        if(node==null){
    
            return null;
        }
        return node.asText();
    }

    public static String getFieldValue(String json , String path){
    
        JsonNode jsonNode = readTree(json);
        return getFieldValue(jsonNode,path);
    }

    public static void main(String[] args){
    
//		Map map = new HashMap();
//		map.put("name", " Zhang San ");
//		map.put("age", 50);
//		map.put(" Birthday ", new Date());
//		System.out.println(writeValueAsString(map));
//		System.out.println(writeValueAsString(map,"yyyy year MM month dd Japan HH when mm branch "));

        String str = "{'username':'admin',password:'000000'}";

//		String str = "{ \"name\" : \" Xiao Yuanshan \", \"sex\" : \" male \", \"age\" : \"23\",\"address\" : \" Zhengzhou, Henan \"}";
        Map<?,?> map = readValue(str,HashMap.class);
        System.out.println(map);
    }