一、json需要依賴的包

 

 

jackson.version可以參考地址：http://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core

 

<!-- jackson -->
<dependency>
	<groupId>com.fasterxml.jackson.core</groupId>
	<artifactId>jackson-core</artifactId>
	<version>${jackson.version}</version>
</dependency>
<dependency>
	<groupId>com.fasterxml.jackson.core</groupId>
	<artifactId>jackson-annotations</artifactId>
	<version>${jackson.version}</version>
</dependency>
<dependency>
	<groupId>com.fasterxml.jackson.core</groupId>
	<artifactId>jackson-databind</artifactId>
	<version>${jackson.version}</version>
</dependency>

 

 

 

二、json反序列化工具類

 

 

 

import java.io.IOException;
import java.util.List;
import java.util.Map;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;

public class JsonUtils {

	// 定義jackson物件
	private static final ObjectMapper MAPPER = new ObjectMapper();
	static {
		// 忽略JSON中沒有的欄位，防止反序列化物件的時候報找不到屬性欄位的異常
		MAPPER.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
		// 如果json字串中含有新行時，加上這個
		MAPPER.configure(JsonParser.Feature.ALLOW_UNQUOTED_CONTROL_CHARS, true);
		//空值轉換異常
		MAPPER.configure(JsonParser.Feature.ALLOW_COMMENTS, true) ;   
	}

	/**
	 * 將物件轉換成json字串。
	 * <p>
	 * Title: pojoToJson
	 * </p>
	 * <p>
	 * Description:
	 * </p>
	 * 
	 * @param data
	 * @return
	 */
	public static String objectToJson(Object data) {
		try {
			String string = MAPPER.writeValueAsString(data);
			return string;
		} catch (JsonProcessingException e) {
			e.printStackTrace();
		}
		return null;
	}

	/**
	 * 將json結果集轉化為物件
	 * 
	 * @param jsonData
	 *            json資料
	 * @param clazz
	 *            物件中的object型別
	 * @return
	 */
	public static <T> T jsonToPojo(String jsonData, Class<T> beanType) {
		try {
			T t = MAPPER.readValue(jsonData, beanType);
			return t;
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}

	/**
	 * 將json資料轉換成pojo物件list
	 * <p>
	 * Title: jsonToList
	 * </p>
	 * <p>
	 * Description:
	 * </p>
	 * 
	 * @param jsonData
	 * @param beanType
	 * @return
	 */
	public static <T> List<T> jsonToList(String jsonData, Class<T> beanType) {
		JavaType javaType = MAPPER.getTypeFactory().constructParametricType(List.class, beanType);
		try {
			List<T> list = MAPPER.readValue(jsonData, javaType);
			return list;
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}
	}

    /**
     * json字串轉Map集合
     * @param jsonStr
     * @return
     * @throws IOException
     */
    @SuppressWarnings("unchecked")
    public static Map<String, Object> parseMap(String jsonStr) throws IOException {
        Map<String, Object> map = MAPPER.readValue(jsonStr, Map.class);
        return map;
    }

    /**
     * json字串轉List集合
     * @param jsonStr
     * @return
     * @throws IOException
     */
    public static List<String> parseList(String jsonStr) throws IOException {
        return MAPPER.readValue(jsonStr, new TypeReference<List<String>>() {});
    }
}