cn.enilu.flash.core.util.JsonUtil Maven / Gradle / Ivy

package cn.enilu.flash.core.util;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.ObjectReader;
import com.fasterxml.jackson.databind.ObjectWriter;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.datatype.joda.JodaModule;

import java.io.Reader;
import java.util.List;
import java.util.TimeZone;

/**
 * json处理工具类
 * @author enilu([email protected])
 */
public final class JsonUtil {
    @SuppressWarnings("serial")
    public static class CodecException extends RuntimeException {
        public CodecException(Throwable cause) {
            super(cause);
        }
    }

    private static final ObjectMapper mapper;
    private static final ObjectReader objectReader;
    private static final ObjectWriter objectWriter;

    static {
        mapper = new ObjectMapper();
        mapper.configure(SerializationFeature.WRITE_NULL_MAP_VALUES, false);
        mapper.registerModule(new JodaModule());

        //see http://wiki.fasterxml.com/JacksonFAQDateHandling
        mapper.setTimeZone(TimeZone.getDefault());//force local timezone

        objectReader = mapper.reader();
        objectWriter = mapper.writer();
    }

    private JsonUtil() {
    }

    public static ObjectMapper getMapper() {
        return mapper;
    }

    /**
     * 将bean 转换为json字符串
     * @param value
     * @return
     * @throws CodecException
     */
    public static String dump(Object value) throws CodecException {
        try {
            return objectWriter.writeValueAsString(value);
        } catch (Exception e) {
            throw new CodecException(e);
        }
    }

    /**
     * 将reader转换为bean
     * @param reader
     * @param type
     * @param 
     * @return
     * @throws CodecException
     */
    public static  T load(Reader reader, Class type) throws CodecException {
        try {
            return objectReader.withType(type).readValue(reader);
        } catch (Exception e) {
            throw new CodecException(e);
        }
    }

    /**
     * 将json字符串转换bean
     * @param json
     * @param type
     * @param 
     * @return
     * @throws CodecException
     */
    public static  T load(String json, Class type) throws CodecException {
        try {
            return objectReader.withType(type).readValue(json);
        } catch (Exception e) {
            throw new CodecException(e);
        }
    }

    /**
     * 将reader转换集合
     * @param reader
     * @param type
     * @param 
     * @return
     * @throws CodecException
     */
    public static  List loadList(Reader reader, Class type) throws CodecException {
        try {
            return objectReader.withType(mapper.getTypeFactory().constructCollectionType(List.class, type))
                    .readValue(reader);
        } catch (Exception e) {
            throw new CodecException(e);
        }
    }

    /**
     * 将json字符串转换为集合
     * @param jsonArray
     * @param type
     * @param 
     * @return
     * @throws CodecException
     */
    public static  List loadList(String jsonArray, Class type) throws CodecException {
        try {
            return objectReader.withType(mapper.getTypeFactory().constructCollectionType(List.class, type))
                    .readValue(jsonArray);
        } catch (Exception e) {
            throw new CodecException(e);
        }
    }

}