Question

我正在尝试升级我的项目以使用更新版本的Jackson，并且遇到了自定义序列化程序和反序列化程序。

在下面的反序列化器中，我遇到了构造函数问题 - 我不确定我应该传入哪种类型。我使用的构造函数不再可用。以下是当前的课程：

import com.fasterxml.jackson.databind.DeserializationContext; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.deser.std.StdKeyDeserializer;

public class SifMapKeyDeserializer扩展了StdKeyDeserializer {

protected SifMapKeyDeserializer(Class<?> cls) {
    super(cls); //IT COMPLAINS.  It needs a type, not sure what type?
}

@Override
protected Object _parse(String key, DeserializationContext ctxt)
        throws Exception {
    ObjectMapper jacksonMapper = ObjectMapperFactory.getObjectMapper();
    JsonNode element =  jacksonMapper.readTree(key);

    String fullClassName = element.path(JacksonExtConstants.JAVA_CLASS_NAME_KEY).asText();
    String nodeText = element.toString();
    Object result = null;
    try {
        result = jacksonMapper.readValue(nodeText, Class.forName(fullClassName));
    } catch (ClassNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    return result;
}

}

编辑我发现这是为了解决上述问题。

public SifMapKeyDeserializer(Class<?> cls) {
    super(StdKeyDeserializer.TYPE_CLASS, cls);
}

下面列出了解串器。我对 AnnotatedMethod 和 SimpleBeanPropertyDefinition 的构建存在问题 - 我不确定如何纠正这些问题。

import java.lang.reflect.Method;
import java.util.List;

import com.fasterxml.jackson.databind.BeanDescription;
import com.fasterxml.jackson.databind.SerializationConfig;
import com.fasterxml.jackson.databind.introspect.AnnotatedMethod;
import com.fasterxml.jackson.databind.introspect.AnnotationMap;
import com.fasterxml.jackson.databind.introspect.BeanPropertyDefinition;
import com.fasterxml.jackson.databind.ser.BeanPropertyWriter;
import com.fasterxml.jackson.databind.ser.BeanSerializerModifier;
import com.fasterxml.jackson.databind.type.SimpleType;
import com.fasterxml.jackson.databind.util.SimpleBeanPropertyDefinition;


/**
 * This custom bean serializer is to allow us add/delete any properties.
 * For example for each deserialized bean we are currently adding its fully 
 * qualified class name.
 *
 */
public class SifBeanSerializerModifier extends BeanSerializerModifier {
    public List<BeanPropertyWriter> changeProperties(SerializationConfig config,
            BeanDescription beanDesc, List<BeanPropertyWriter> beanProperties) {

            Class cc = beanDesc.getType().getRawClass();      
            Method m;
            try {
                m = cc.getMethod("getClass", null);
                AnnotatedMethod am = new AnnotatedMethod(m, _emptyAnnotationMap(), null);
                BeanPropertyDefinition propDef = new SimpleBeanPropertyDefinition(am, JacksonExtConstants.JAVA_CLASS_NAME_KEY);
                BeanPropertyWriter beanPropWriter = new BeanPropertyWriter(propDef,
                            am, null,
                            SimpleType.constructUnsafe(Class.class),
                            null, null, SimpleType.constructUnsafe(Class.class),
                            true, null);

                beanProperties.add(beanPropWriter);
            } catch (SecurityException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (NoSuchMethodException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }      
        return beanProperties;
    }


    private AnnotationMap _emptyAnnotationMap() {
        return new AnnotationMap();
    }
}

非常感谢任何帮助。

由于

Answer 1

我能够像这样修复它::

public class SifBeanSerializerModifier extends BeanSerializerModifier {
public List<BeanPropertyWriter> changeProperties(SerializationConfig config,
        BeanDescription beanDesc, List<BeanPropertyWriter> beanProperties) {

        Class cc = beanDesc.getType().getRawClass();      
        Method m;
        try {
            m = cc.getMethod("getClass", null);
            TypeResolutionContext.Basic tb = new TypeResolutionContext.Basic(TypeFactory.defaultInstance(), TypeBindings.emptyBindings());
            AnnotatedMethod am = new AnnotatedMethod(tb, m, _emptyAnnotationMap(), null);
            BeanPropertyDefinition propDef = SimpleBeanPropertyDefinition.construct(config, am, JacksonExtConstants.JAVA_CLASS_NAME_KEY);
            BeanPropertyWriter beanPropWriter = new BeanPropertyWriter(propDef,
                        am, null,
                        SimpleType.constructUnsafe(Class.class),
                        null, null, SimpleType.constructUnsafe(Class.class),
                        true, null);

            beanProperties.add(beanPropWriter);
        } catch (SecurityException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (NoSuchMethodException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }      
    return beanProperties;
}


private AnnotationMap _emptyAnnotationMap() {
    return new AnnotationMap();
}

}

杰克逊从2.0.4升级到2.7.1

1 个答案: