package org.konghao.basic.util; import java.io.IOException;
import java.io.StringWriter; import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper; public class JsonUtil {
private static JsonUtil ju;
private static JsonFactory jf;
private static ObjectMapper mapper; private JsonUtil() {
} public static JsonUtil getInstance() {
if (ju == null)
ju = new JsonUtil();
return ju;
} public static ObjectMapper getMapper() {
if (mapper == null) {
mapper = new ObjectMapper();
}
return mapper;
} public static JsonFactory getFactory() {
if (jf == null)
jf = new JsonFactory();
return jf;
} public String obj2json(Object obj) {
JsonGenerator jg = null;
try {
jf = getFactory();
mapper = getMapper();
StringWriter out = new StringWriter();
jg = jf.createJsonGenerator(out);
mapper.writeValue(jg, obj);
return out.toString();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (jg != null)
jg.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
} public Object json2obj(String json, Class<?> clz) {
try {
mapper = getMapper();
return mapper.readValue(json, clz);
} catch (JsonParseException e) {
e.printStackTrace();
} catch (JsonMappingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
} }