[MPIR-404] Warn and accept invalid mailing list links

This closes #28

src/main/java/org/apache/maven/report/projectinfo/MailingListsReport.java

@@ -22,6 +22,7 @@
 import org.apache.maven.doxia.sink.Sink;
 import org.apache.maven.model.MailingList;
 import org.apache.maven.model.Model;
+import org.apache.maven.plugin.logging.Log;
 import org.apache.maven.plugins.annotations.Mojo;
 import org.codehaus.plexus.i18n.I18N;
 import org.codehaus.plexus.util.StringUtils;
@@ -63,7 +64,7 @@ public boolean canGenerateReport()
     public void executeReport( Locale locale )
     {
         MailingListsRenderer r =
-            new MailingListsRenderer( getSink(), getProject().getModel(), getI18N( locale ), locale );
+            new MailingListsRenderer( getLog(), getSink(), getProject().getModel(), getI18N( locale ), locale );
 
         r.render();
     }
@@ -92,13 +93,15 @@ protected String getI18Nsection()
     protected static class MailingListsRenderer
         extends AbstractProjectInfoRenderer
     {
+
+        private final Log log;
         private final Model model;
 
-        MailingListsRenderer( Sink sink, Model model, I18N i18n, Locale locale )
+        MailingListsRenderer( Log log, Sink sink, Model model, I18N i18n, Locale locale )
         {
             super( sink, i18n, locale );
             this.model = model;
-
+            this.log = log;
         }
 
         @Override
@@ -279,14 +282,22 @@ private String createURILinkPatternedText( String text, String href, String defa
                 return createLinkPatternedText( text, defaultHref );
             }
 
-            URI hrefUri = URI.create( href );
-            if ( StringUtils.isNotEmpty( hrefUri.getScheme() ) )
+            try
             {
-                return createLinkPatternedText( text, href );
+                URI hrefUri = URI.create( href );
+                if ( StringUtils.isNotEmpty( hrefUri.getScheme() ) )
+                {
+                    return createLinkPatternedText( text, href );
+                }
+                else
+                {
+                    return createLinkPatternedText( text, "mailto:" + href );
+                }
             }
-            else
+            catch ( IllegalArgumentException e )
             {
-                return createLinkPatternedText( text, "mailto:" + href );
+                log.warn( "Invalid mailing list link provided '" + href + "': " + e.getMessage() );
+                return href;
             }
         }
     }

src/test/java/org/apache/maven/report/projectinfo/MailingListsReportTest.java

@@ -111,4 +111,16 @@ public void testFrenchReport()
             Locale.setDefault( oldLocale );
         }
     }
+
+    /**
+     * Test invalid links (MPIR-404)
+     * Those should only lead to a WARN but not an exception
+     * @throws Exception if any
+     */
+    public void testInvalidLink()
+        throws Exception
+    {
+        generateReport( "mailing-lists", "mailing-lists-plugin-config-invalidlink.xml" );
+        assertTrue( "Test html generated", getGeneratedReport( "mailing-lists.html" ).exists() );
+    }
 }

src/test/java/org/apache/maven/report/projectinfo/stubs/MailingListsInvalidLinkStub.java

@@ -0,0 +1,30 @@
+package org.apache.maven.report.projectinfo.stubs;
+
+/*
+ * 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.
+ */
+
+public class MailingListsInvalidLinkStub
+    extends ProjectInfoProjectStub
+{
+    @Override
+    protected String getPOM()
+    {
+        return "mailing-lists-plugin-config-invalidlink.xml";
+    }
+}

src/test/resources/plugin-configs/mailing-lists-plugin-config-invalidlink.xml

@@ -0,0 +1,55 @@
+<!--
+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.
+-->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>org.apache.maven.plugin.projectinfo.tests</groupId>
+  <artifactId>mailing-lists</artifactId>
+  <version>1.0-SNAPSHOT</version>
+  <packaging>jar</packaging>
+  <name>mailing lists project info</name>
+  <dependencies>
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>3.8.1</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+  <mailingLists>
+    <mailingList>
+      <name>Test List</name>
+      <!-- invalid link to prevent easy scraping -->
+      <post>test at maven.apache.org</post>
+      <subscribe>MAILTO:test-subscribe@maven.apache.org</subscribe>
+    </mailingList>
+  </mailingLists>
+  <build>
+    <plugins>
+      <plugin>
+        <artifactId>maven-project-info-reports-plugin</artifactId>
+        <configuration>
+          <outputDirectory>target/test-harness/mailing-lists</outputDirectory>
+          <localRepository>${localRepository}</localRepository>
+          <project implementation="org.apache.maven.report.projectinfo.stubs.MailingListsInvalidLinkStub"/>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+</project>