Remove servlet-api from WAR/lib

It is wrong to include the servlet API in a WAR's WEB-INF/lib
directory. This confuses some servlet containers who refuse to
load the Gerrit WAR. Instead package the Jetty runtime and the
servlet API in a new WEB-INF/pgm-lib directory.

Change-Id: Ic5fe14c735e781b2d78d2fa8d0d403a08b7ee21f

gerrit-launcher/src/main/java/com/google/gerrit/launcher/GerritLauncher.java

@@ -206,27 +206,10 @@ public final class GerritLauncher {
           final ZipEntry ze = e.nextElement();
           if (ze.isDirectory()) {
             continue;
-          }
-
-          if (ze.getName().startsWith("WEB-INF/lib/")) {
-            String name = ze.getName().substring("WEB-INF/lib/".length());
-            final File tmp = createTempFile(safeName(ze), ".jar");
-            final FileOutputStream out = new FileOutputStream(tmp);
-            try {
-              final InputStream in = zf.getInputStream(ze);
-              try {
-                final byte[] buf = new byte[4096];
-                int n;
-                while ((n = in.read(buf, 0, buf.length)) > 0) {
-                  out.write(buf, 0, n);
-                }
-              } finally {
-                in.close();
-              }
-            } finally {
-              out.close();
-            }
-            jars.put(name, tmp.toURI().toURL());
+          } else if (ze.getName().startsWith("WEB-INF/lib/")) {
+            extractJar(zf, ze, jars);
+          } else if (ze.getName().startsWith("WEB-INF/pgm-lib/")) {
+            extractJar(zf, ze, jars);
           }
         }
       } finally {
@@ -261,6 +244,31 @@ public final class GerritLauncher {
         parent);
   }
 
+  private static void extractJar(ZipFile zf, ZipEntry ze,
+      SortedMap<String, URL> jars) throws IOException {
+    File tmp = createTempFile(safeName(ze), ".jar");
+    FileOutputStream out = new FileOutputStream(tmp);
+    try {
+      InputStream in = zf.getInputStream(ze);
+      try {
+        byte[] buf = new byte[4096];
+        int n;
+        while ((n = in.read(buf, 0, buf.length)) > 0) {
+          out.write(buf, 0, n);
+        }
+      } finally {
+        in.close();
+      }
+    } finally {
+      out.close();
+    }
+
+    String name = ze.getName();
+    jars.put(
+        name.substring(name.lastIndexOf('/'), name.length()),
+        tmp.toURI().toURL());
+  }
+
   private static void move(SortedMap<String, URL> jars,
       String prefix,
       List<URL> extapi) {

gerrit-war/pom.xml

@@ -40,6 +40,12 @@ limitations under the License.
       <scope>provided</scope>
     </dependency>
 
+    <dependency>
+      <groupId>org.apache.tomcat</groupId>
+      <artifactId>tomcat-servlet-api</artifactId>
+      <scope>provided</scope>
+    </dependency>
+
     <dependency>
       <groupId>com.google.gerrit</groupId>
       <artifactId>gerrit-gwtui</artifactId>
@@ -99,6 +105,18 @@ limitations under the License.
       <groupId>com.google.gerrit</groupId>
       <artifactId>gerrit-pgm</artifactId>
       <version>${project.version}</version>
+      <exclusions>
+        <exclusion>
+          <groupId>org.eclipse.jetty</groupId>
+          <artifactId>jetty-servlet</artifactId>
+        </exclusion>
+      </exclusions>
+    </dependency>
+
+    <dependency>
+      <groupId>org.eclipse.jetty</groupId>
+      <artifactId>jetty-servlet</artifactId>
+      <scope>provided</scope>
     </dependency>
   </dependencies>
 
@@ -133,10 +151,47 @@ limitations under the License.
         </configuration>
       </plugin>
 
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-dependency-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>copy-servlet-api</id>
+            <configuration>
+              <includeGroupIds>org.apache.tomcat,org.eclipse.jetty</includeGroupIds>
+              <excludeArtifactIds>servlet-api</excludeArtifactIds>
+            </configuration>
+            <goals>
+              <goal>copy-dependencies</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
+
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-antrun-plugin</artifactId>
         <executions>
+          <execution>
+            <id>copy-servlet-api</id>
+            <phase>process-classes</phase>
+            <configuration>
+              <target>
+                <property name="src" location="${project.build.directory}/dependency" />
+                <property name="dst" location="${project.build.directory}/${project.build.finalName}/WEB-INF/pgm-lib" />
+
+                <mkdir dir="${dst}" />
+                <copy overwrite="true" todir="${dst}">
+                  <fileset dir="${src}">
+                    <include name="*.jar" />
+                  </fileset>
+                </copy>
+              </target>
+            </configuration>
+            <goals>
+              <goal>run</goal>
+            </goals>
+          </execution>
           <execution>
             <id>copy-license</id>
             <phase>process-classes</phase>

pom.xml

@@ -371,7 +371,7 @@ limitations under the License.
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-dependency-plugin</artifactId>
-          <version>2.1</version>
+          <version>2.5.1</version>
         </plugin>
 
         <plugin>