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/* * 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 * * https://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 {@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. */ 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 {@code NestedServletException} with the specified detail message. * @param msg the detail message */ public NestedServletException(String msg) { super(msg); } /** * 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. */ @Override @Nullable public String getMessage() { return NestedExceptionUtils.buildMessage(super.getMessage(), getCause()); } }