Introduce a new class - MultiThrowable - to report exceptions when mu…

…ltiple actions are taken where each action may throw an exception but all actions are taken before any errors are reported. Use this new class when reporting multiple container (e.g. web application) failures during start.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1837133 13f79535-47bb-0310-9956-ffa450edef68

java/org/apache/catalina/core/ContainerBase.java

@@ -64,6 +64,7 @@
 import org.apache.juli.logging.Log;
 import org.apache.juli.logging.LogFactory;
 import org.apache.tomcat.util.ExceptionUtils;
+import org.apache.tomcat.util.MultiThrowable;
 import org.apache.tomcat.util.res.StringManager;
 import org.apache.tomcat.util.threads.InlineExecutorService;
 
@@ -943,31 +944,32 @@ protected synchronized void startInternal() throws LifecycleException {
             results.add(startStopExecutor.submit(new StartChild(children[i])));
         }
 
-        boolean fail = false;
+        MultiThrowable multiThrowable = new MultiThrowable();
+
         for (Future<Void> result : results) {
             try {
                 result.get();
-            } catch (Exception e) {
+            } catch (Throwable e) {
                 log.error(sm.getString("containerBase.threadedStartFailed"), e);
-                fail = true;
+                multiThrowable.add(e);
             }
 
         }
-        if (fail) {
-            throw new LifecycleException(
-                    sm.getString("containerBase.threadedStartFailed"));
+        if (multiThrowable.size() > 0) {
+            throw new LifecycleException(sm.getString("containerBase.threadedStartFailed"),
+                    multiThrowable.getThrowable());
         }
 
         // Start the Valves in our pipeline (including the basic), if any
-        if (pipeline instanceof Lifecycle)
+        if (pipeline instanceof Lifecycle) {
             ((Lifecycle) pipeline).start();
+        }
 
 
         setState(LifecycleState.STARTING);
 
         // Start our thread
         threadStart();
-
     }
 
 

java/org/apache/tomcat/util/MultiThrowable.java

@@ -0,0 +1,97 @@
+/*
+ *  Licensed to the Apache Software Foundation (ASF) under one or more
+ *  contributor license agreements.  See the NOTICE file distributed with
+ *  this work for additional information regarding copyright ownership.
+ *  The ASF licenses this file to You 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.apache.tomcat.util;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Wraps a list of throwables as a single throwable. This is intended to be used
+ * when multiple actions are taken where each may throw an exception but all
+ * actions are taken before any errors are reported.
+ */
+public class MultiThrowable extends Throwable {
+
+    private static final long serialVersionUID = 1L;
+
+    private List<Throwable> throwables = new ArrayList<>();
+
+    /**
+     * Add a throwable to the list of wrapped throwables.
+     *
+     * @param t The throwable to add
+     */
+    public void add(Throwable t) {
+        throwables.add(t);
+    }
+
+
+    /**
+     * @return A read-only list of the wrapped throwables.
+     */
+    public List<Throwable> getThrowables() {
+        return Collections.unmodifiableList(throwables);
+    }
+
+
+    /**
+     * @return {@code null} if there are no wrapped throwables, the Throwable if
+     *         there is a single wrapped throwable or the current instance of
+     *         there are multiple wrapped throwables
+     */
+    public Throwable getThrowable() {
+        if (size() == 0) {
+            return null;
+        } else if (size() == 1) {
+            return throwables.get(0);
+        } else {
+            return this;
+        }
+    }
+
+
+    /**
+     * @return The number of throwables currently wrapped by this instance.
+     */
+    public int size() {
+        return throwables.size();
+    }
+
+
+    /**
+     * Overrides the default implementation to provide a concatenation of the
+     * messages associated with each of the wrapped throwables. Note that the
+     * format of the returned String is not guaranteed to be fixed and may
+     * change in a future release.
+     */
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append(super.toString());
+        sb.append(": ");
+        sb.append(size());
+        sb.append(" wrapped Throwables: ");
+        for (Throwable t : throwables) {
+            sb.append("[");
+            sb.append(t.getMessage());
+            sb.append("]");
+        }
+
+        return sb.toString();
+    }
+}

test/org/apache/catalina/startup/TestTomcat.java

@@ -38,10 +38,14 @@
 import org.apache.catalina.Context;
 import org.apache.catalina.Host;
 import org.apache.catalina.LifecycleEvent;
+import org.apache.catalina.LifecycleException;
 import org.apache.catalina.LifecycleListener;
+import org.apache.catalina.authenticator.AuthenticatorBase;
+import org.apache.catalina.connector.Request;
 import org.apache.catalina.core.StandardContext;
 import org.apache.catalina.core.StandardHost;
 import org.apache.catalina.ha.context.ReplicatedContext;
+import org.apache.tomcat.util.MultiThrowable;
 import org.apache.tomcat.util.buf.ByteChunk;
 import org.apache.tomcat.util.descriptor.web.ContextEnvironment;
 import org.apache.tomcat.util.descriptor.web.ContextResourceLink;
@@ -554,4 +558,65 @@ public void lifecycleEvent(LifecycleEvent event) {
             used = true;
         }
     }
+
+
+    @Test
+    public void testBrokenWarOne() throws Exception {
+        Tomcat tomcat = getTomcatInstance();
+
+        StandardContext ctx = (StandardContext) tomcat.addContext("/a", null);
+        ctx.addValve(new BrokenAuthenticator());
+
+        try {
+            tomcat.start();
+            Assert.fail();
+        } catch (Throwable t) {
+            Assert.assertTrue(getRootCause(t) instanceof LifecycleException);
+        }
+    }
+
+
+    @Test
+    public void testBrokenWarTwo() throws Exception {
+        Tomcat tomcat = getTomcatInstance();
+
+        StandardContext ctxA = (StandardContext) tomcat.addContext("/a", null);
+        ctxA.addValve(new BrokenAuthenticator());
+        StandardContext ctxB = (StandardContext) tomcat.addContext("/b", null);
+        ctxB.addValve(new BrokenAuthenticator());
+
+        try {
+            tomcat.start();
+            Assert.fail();
+        } catch (Throwable t) {
+            Assert.assertTrue(getRootCause(t) instanceof MultiThrowable);
+        }
+    }
+
+
+    private static Throwable getRootCause(Throwable t) {
+        while (t.getCause() != null && t.getCause() != t) {
+            t = t.getCause();
+        }
+        return t;
+    }
+
+
+    private static class BrokenAuthenticator extends AuthenticatorBase {
+
+        @Override
+        protected boolean doAuthenticate(Request request, HttpServletResponse response) throws IOException {
+            return false;
+        }
+
+        @Override
+        protected String getAuthMethod() {
+            return null;
+        }
+
+        @Override
+        protected synchronized void startInternal() throws LifecycleException {
+            throw new LifecycleException("Deliberately Broken");
+        }
+    }
 }

webapps/docs/changelog.xml

@@ -70,6 +70,13 @@
         <bug>62527</bug>: Revert restriction of JNDI to the <code>java:</code>
         namespace. (remm)
       </fix>
+      <add>
+        Introduce a new class - <code>MultiThrowable</code> - to report
+        exceptions when multiple actions are taken where each action may throw
+        an exception but all actions are taken before any errors are reported.
+        Use this new class when reporting multiple container (e.g. web
+        application) failures during start. (markt)
+      </add>
     </changelog>
   </subsection>
   <subsection name="Coyote">