java - 如何捕获 NoSuchMethodException

Question

我正在尝试反序列化包含方法的 XML 文件。 片段如下:

 XMLDecoder decoder = new XMLDecoder(os); 
    deSerializedObject = decoder.readObject(); 
    decoder.close();
    return deSerializedObject;

当 XML 文件不包含每个对象的方法时。它会抛出 NoSuchMethodException @ readObject。

java.lang.NoSuchMethodException: No method with name add is found at java.beans.Statement.findMethod(Statement.java:454) at java.beans.Statement.invokeMethodImpl(Statement.java:247) at java.beans.Statement.access$000(Statement.java:46) at java.beans.Statement$1.run(Statement.java:130) at java.security.AccessController.doPrivileged(AccessController.java:284) at java.beans.Statement.invokeMethod(Statement.java:127) at java.beans.Expression.getValue(Expression.java:67) at java.beans.XMLDecoder$SAXHandler.executeCommon(XMLDecoder.java:392) at java.beans.XMLDecoder$SAXHandler.execute(XMLDecoder.java:321) at java.beans.XMLDecoder$SAXHandler.endElement(XMLDecoder.java:286) at org.apache.xerces.parsers.AbstractSAXParser.endElement(Unknown Source) at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanEndElement(Unknown Source) at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(Unknown Source) at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source) at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source) at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source) at org.apache.xerces.parsers.XMLParser.parse(Unknown Source) at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
at org.apache.xerces.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source) at org.apache.xerces.jaxp.SAXParserImpl.parse(Unknown Source) at javax.xml.parsers.SAXParser.parse(Unknown Source) at java.beans.XMLDecoder.readObject(XMLDecoder.java:662)

问题是我无法捕获这个异常。正确的处理方法是什么？

try{
        deSerializedObject = decoder.readObject();
        System.out.println("We are after read object");
        }
        catch (NoSuchMethodException e)
        {
            System.out.println("We are in catch block !!");
            e.printStackTrace();
        }
        decoder.close();
        return deSerializedObject;

这里的错误是“NoSuchMethodException 无法到达的 catch block 。这个异常永远不会从 try 语句主体中抛出”

XML 看起来像

<?xml version="1.0" encoding="UTF-8"?>
<java version="1.6.0" class="java.beans.XMLDecoder">
 <object class="java.util.ArrayList">
  <void method="add">
   <object class="InfoParameters">
    <void property="Name">
     <string>Jay</string>
    </void>
     <void property="Level">
     <string>10</string>
    </void>
   </object>
   <object class="InfoParameters">
    <void property="Name">
     <string>Hir</string>
    </void>
    <void property="Level">
     <string>10</string>
    </void>
   </object>
  </void>
 </object>
</java>

Answer 1

为什么你不能捕获这个异常？

XMLDecoder decoder = new XMLDecoder(os); 

try
{
    deSerializedObject = decoder.readObject(); 
}
catch(NoSuchMethodException nsme)
{
    System.err.println(nsme.getMessage());
}
catch(Exception e)
{
    //try me
}

decoder.close();
return deSerializedObject;