/*
 * Copyright 2002-2018 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License 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 org.springframework.web.util;

import javax.servlet.ServletException;

import org.springframework.core.NestedExceptionUtils;
import org.springframework.lang.Nullable;

Subclass of ServletException that properly handles a root cause in terms of message and stacktrace, just like NestedChecked/RuntimeException does. 
Note that the plain ServletException doesn't expose its root cause at all,
neither in the exception message nor in printed stack traces! While this might
be fixed in later Servlet API variants (which even differ per vendor for the
same API version), it is not reliably available on Servlet 2.4 (the minimum
version required by Spring 3.x), which is why we need to do it ourselves.
The similarity between this class and the NestedChecked/RuntimeException
class is unavoidable, as this class needs to derive from ServletException.
Author:
Juergen Hoeller
See Also:
getMessage
Throwable.printStackTrace
NestedCheckedException
NestedRuntimeException
Since:
1.2.5/**
 * Subclass of {@link ServletException} that properly handles a root cause in terms
 * of message and stacktrace, just like NestedChecked/RuntimeException does.
 *
 * <p>Note that the plain ServletException doesn't expose its root cause at all,
 * neither in the exception message nor in printed stack traces! While this might
 * be fixed in later Servlet API variants (which even differ per vendor for the
 * same API version), it is not reliably available on Servlet 2.4 (the minimum
 * version required by Spring 3.x), which is why we need to do it ourselves.
 *
 * <p>The similarity between this class and the NestedChecked/RuntimeException
 * class is unavoidable, as this class needs to derive from ServletException.
 *
 * @author Juergen Hoeller
 * @since 1.2.5
 * @see #getMessage
 * @see #printStackTrace
 * @see org.springframework.core.NestedCheckedException
 * @see org.springframework.core.NestedRuntimeException
 */
public class NestedServletException extends ServletException {

	
Use serialVersionUID from Spring 1.2 for interoperability. /** Use serialVersionUID from Spring 1.2 for interoperability. */
	private static final long serialVersionUID = -5292377985529381145L;

	static {
		// Eagerly load the NestedExceptionUtils class to avoid classloader deadlock
		// issues on OSGi when calling getMessage(). Reported by Don Brown; SPR-5607.
		NestedExceptionUtils.class.getName();
	}


	
Construct a NestedServletException with the specified detail message. 
Params:
msg – the detail message/**
	 * Construct a {@code NestedServletException} with the specified detail message.
	 * @param msg the detail message
	 */
	public NestedServletException(String msg) {
		super(msg);
	}

	
Construct a NestedServletException with the specified detail message and nested exception. 
Params:
msg – the detail message
cause – the nested exception/**
	 * Construct a {@code NestedServletException} with the specified detail message
	 * and nested exception.
	 * @param msg the detail message
	 * @param cause the nested exception
	 */
	public NestedServletException(@Nullable String msg, @Nullable Throwable cause) {
		super(msg, cause);
	}


	
Return the detail message, including the message from the nested exception
if there is one.
/**
	 * Return the detail message, including the message from the nested exception
	 * if there is one.
	 */
	@Override
	@Nullable
	public String getMessage() {
		return NestedExceptionUtils.buildMessage(super.getMessage(), getCause());
	}

}