java字符串和对象相互转化

利用jackson-mapper-asl.jar实现对象和json格式的字符串之间的相互转换,在pom.xml文件中引入：

    org.codehaus.jackson
    jackson-core-asl
    1.9.13


    org.codehaus.jackson
    jackson-mapper-asl
    1.9.13

代码实现：

import org.codehaus.jackson.map.DeserializationConfig;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.map.SerializationConfig;
import org.codehaus.jackson.map.annotate.JsonSerialize;
import org.codehaus.jackson.map.ser.impl.SimpleFilterProvider;
import org.codehaus.jackson.type.TypeReference;

/**
 * String和对象相互转化工具
 */
public class JsonMapper {

    private static ObjectMapper objectMapper = new ObjectMapper();

    static {
        // config
        objectMapper.disable(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES);
        objectMapper.configure(SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS, false);
        objectMapper.setFilters(new SimpleFilterProvider().setFailOnUnknownId(false));
        objectMapper.setSerializationInclusion(JsonSerialize.Inclusion.NON_EMPTY);
    }

    public static  String obj2String(T src) {
        if (src == null) {
            return null;
        }
        try {
            return src instanceof String ? (String) src : objectMapper.writeValueAsString(src);
        } catch (Exception e) {
            log.warn("parse object to String exception, error:{}", e);
            return null;
        }
    }

    public static  T string2Obj(String src, TypeReference typeReference) {
        if (src == null || typeReference == null) {
            return null;
        }
        try {
            return (T) (typeReference.getType().equals(String.class) ? src : objectMapper.readValue(src, typeReference));
        } catch (Exception e) {
            log.warn("parse String to Object exception, String:{}, TypeReference:{}, error:{}", src, typeReference.getType(), e);
            return null;
        }
    }
}