Java設置XStream反序列化規則

Question

我有一些類與codeBased enum提交。我有這個類的xml serealized對象。但是，當我嘗試反序列化這個XML與XStream我收到：

com.thoughtworks.xstream.converters.ConversionException：沒有枚舉常量com.functest.util.TriState.0：沒有枚舉常量com.functest.util .TriState.0

類

class Params{ 
    String clientCode; 
    TriState triState; 
} 

xmlParameters字符串

<Params> 
    <clientCode>1516001</clientCode> 
    <triState>0</triState> 
</Params> 

TriState

enum TriState implements codeBased{ 
    YES(1); 
    NO(0); 
    UNDEFINED(-1); 

    int code; 

    TriState fromCode(int code){ 
     if(code == 1) return YES; 
     if(code == 0) return NO; 
     return UNDEFINED; 
    } 
} 

我嘗試反序列化XML這樣的：

XStream xStream = new XStream(); 
xStream.alias("triState", TriState.class); 
Params p = (Params) xStream.fromXML(xmlParameters); 

如何設置反序列化規則，從XML中獲取價值和調用枚舉法fromCode(0)？

Answer 1

將您fromCode到一個靜態方法：

public enum TriState { 
    YES(1),NO(0),UNDEFINED(-1); 
    int code; 
    private TriState(int code) { 
     this.code = code; 
    } 
    public static TriState fromCode(int code) { 
     if (code == 1) 
      return YES; 
     if (code == 0) 
      return NO; 
     return UNDEFINED; 
    } 
} 

，並定義使用靜態方法來代碼轉換爲一個有效的枚舉一個轉換器：

public class TriStateConverter implements Converter { 
    public boolean canConvert(Class type) { 
     return TriState.class==type; 
    } 
    public void marshal(Object o, HierarchicalStreamWriter writer, MarshallingContext mc) { 
     writer.setValue(Integer.toString(((TriState)o).code)); 
    } 
    public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext uc) { 
     return TriState.fromCode(Integer.parseInt(reader.getValue())); 
    } 
} 

沒有嘗試過的代碼，但它應該工作。