代码语言：javascript复制
package org.jeeyxy.util;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.converter.json.MappingJacksonValue;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
public class JsonUtils {
private static Logger logger = LoggerFactory.getLogger(JsonUtils.class);
private final static ObjectMapper objectMapper = new ObjectMapper();
private JsonUtils() {
}
public static ObjectMapper getInstance() {
return objectMapper;
}
/**
* javaBean,list,array convert to json string
*/
public static String toJson(Object obj) {
try {
return objectMapper.writeValueAsString(obj);
} catch (Exception ex) {
logger.warn("write to json string error:" obj, ex);
return null;
}
}
/**
* json string convert to javaBean
*/
public static <T> T toBean(String jsonStr, Class<T> clazz) throws Exception {
return objectMapper.readValue(jsonStr, clazz);
}
/**
* json string convert to map
*/
public static <T> Map<String, Object> toMap(String jsonStr) throws Exception {
if (jsonStr != null && !"".equals(jsonStr)) {
return objectMapper.readValue(jsonStr, Map.class);
} else {
return null;
}
}
/**
* json string convert to map with javaBean
*/
public static <T> Map<String, T> toMapBean(String jsonStr, Class<T> clazz) throws Exception {
Map<String, Map<String, Object>> map = objectMapper.readValue(jsonStr, new TypeReference<Map<String, T>>() {
});
Map<String, T> result = new HashMap<String, T>();
for (Entry<String, Map<String, Object>> entry : map.entrySet()) {
result.put(entry.getKey(), mapToBean(entry.getValue(), clazz));
}
return result;
}
/**
* json array string convert to list with javaBean
*/
public static <T> List<T> toList(String jsonArrayStr, Class<T> clazz) throws Exception {
List<Map<String, Object>> list = objectMapper.readValue(jsonArrayStr, new TypeReference<List<T>>() {
});
List<T> result = new ArrayList<T>();
for (Map<String, Object> map : list) {
result.add(mapToBean(map, clazz));
}
return result;
}
/**
* map convert to javaBean
*/
public static <T> T mapToBean(Map map, Class<T> clazz) {
return objectMapper.convertValue(map, clazz);
}
public static MappingJacksonValue jsonp(Object value,String callback){
MappingJacksonValue mappingJacksonValue = new MappingJacksonValue(value);
mappingJacksonValue.setJsonpFunction(callback);
return mappingJacksonValue;
}
}
