/*
* Copyright 2010-2012 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file is distributed
* on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language governing
* permissions and limitations under the License.
*/
package com.amazonaws.transform;
import java.lang.reflect.Constructor;
import org.w3c.dom.Node;
import com.amazonaws.AmazonServiceException;
import com.amazonaws.AmazonServiceException.ErrorType;
import com.amazonaws.util.XpathUtils;
/**
* Unmarshalls an AWS error response into an AmazonServiceException, or
* optionally, a subclass of AmazonServiceException if this class is extended.
*/
public class LegacyErrorUnmarshaller implements Unmarshaller<AmazonServiceException, Node> {
/**
* The type of AmazonServiceException that will be instantiated. Subclasses
* specialized for a specific type of exception can control this through the
* protected constructor.
*/
private final Class<? extends AmazonServiceException> exceptionClass;
/**
* Constructs a new unmarshaller that will unmarshall AWS error responses as
* a generic AmazonServiceException object.
*/
public LegacyErrorUnmarshaller() {
this(AmazonServiceException.class);
}
/**
* Constructor allowing subclasses to specify a specific type of
* AmazonServiceException to instantiating when populating the exception
* object with data from the AWS error response.
*
* @param exceptionClass
* The class of AmazonServiceException to create and populate
* when unmarshalling the AWS error response.
*/
protected LegacyErrorUnmarshaller(Class<? extends AmazonServiceException> exceptionClass) {
this.exceptionClass = exceptionClass;
}
/* (non-Javadoc)
* @see com.amazonaws.transform.Unmarshaller#unmarshall(java.lang.Object)
*/
public AmazonServiceException unmarshall(Node in) throws Exception {
String errorCode = parseErrorCode(in);
String message = XpathUtils.asString("Response/Errors/Error/Message", in);
String requestId = XpathUtils.asString("Response/RequestID", in);
String errorType = XpathUtils.asString("Response/Errors/Error/Type", in);
Constructor<? extends AmazonServiceException> constructor = exceptionClass.getConstructor(String.class);
AmazonServiceException ase = constructor.newInstance(message);
ase.setErrorCode(errorCode);
ase.setRequestId(requestId);
if (errorType == null) {
ase.setErrorType(ErrorType.Unknown);
} else if (errorType.equalsIgnoreCase("server")) {
ase.setErrorType(ErrorType.Service);
} else if (errorType.equalsIgnoreCase("client")) {
ase.setErrorType(ErrorType.Client);
}
return ase;
}
/**
* Returns the AWS error code for the specified error response.
*
* @param in
* The DOM tree node containing the error response.
*
* @return The AWS error code contained in the specified error response.
*
* @throws Exception
* If any problems were encountered pulling out the AWS error
* code.
*/
public String parseErrorCode(Node in) throws Exception {
return XpathUtils.asString("Response/Errors/Error/Code", in);
}
/**
* Returns the path to the specified property within an error response.
*
* @param property
* The name of the desired property.
*
* @return The path to the specified property within an error message.
*/
public String getErrorPropertyPath(String property) {
return "Response/Errors/Error/" + property;
}
}