Include jars from the manifest's classpath into the classloader

PR:	6921


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@273881 13f79535-47bb-0310-9956-ffa450edef68

src/main/org/apache/tools/ant/AntClassLoader.java

@@ -390,6 +390,8 @@ public class AntClassLoader extends ClassLoader implements BuildListener {
     /**
      * Set the parent for this class loader. This is the class loader to which
      * this class loader will delegate to load classes
+     *
+     * @param parent the parent class loader.
      */
     public void setParent(ClassLoader parent) {
         if (parent == null) {
@@ -400,9 +402,12 @@ public class AntClassLoader extends ClassLoader implements BuildListener {
     }
 
     /**
-     * Control whether class ookup is delegated to the parent loader first
+     * Control whether class lookup is delegated to the parent loader first
      * or after this loader. Use with extreme caution. Setting this to 
      * false violates the class loader hierarchy and can lead to Linkage errors
+     *
+     * @param parentFirst if true, delegate initial class search to the parent
+     *                    classloader.
      */
     public void setParentFirst(boolean parentFirst) {
         this.parentFirst = parentFirst;
@@ -472,6 +477,22 @@ public class AntClassLoader extends ClassLoader implements BuildListener {
         File pathComponent
             = project != null ? project.resolveFile(pathElement)
                               : new File(pathElement);
+        try {
+            addPathFile(pathComponent);
+        } catch (IOException e) {
+            throw new BuildException(e);
+        }
+    }
+    
+    /**
+     * Add a file to the path
+     *
+     * @param pathComponent the file which is to be added to the path for
+     *                      this class loader
+     *
+     * @throws IOException if data needed from the file cannot be read.
+     */
+    protected void addPathFile(File pathComponent) throws IOException { 
         pathComponents.addElement(pathComponent);
     }
 
@@ -965,12 +986,12 @@ public class AntClassLoader extends ClassLoader implements BuildListener {
         if (isParentFirst(classname)) {
             try {
                 theClass = findBaseClass(classname);
-                log("Class " + classname + " loaded from parent loader ( parentFirst )",
-                    Project.MSG_DEBUG);
+                log("Class " + classname + " loaded from parent loader " 
+                    + "(parentFirst)", Project.MSG_DEBUG);
             } catch (ClassNotFoundException cnfe) {
                 theClass = findClass(classname);
-                log("Class " + classname + " loaded from ant loader ( parentFirst )",
-                    Project.MSG_DEBUG);
+                log("Class " + classname + " loaded from ant loader " 
+                    + "(parentFirst)", Project.MSG_DEBUG);
             }
         } else {
             try {
@@ -1015,6 +1036,10 @@ public class AntClassLoader extends ClassLoader implements BuildListener {
      *
      * @param classData the bytecode data for the class
      * @param classname the name of the class
+     *
+     * @return the Class instance created from the given data
+     *
+     * @throws IOException if the class data cannot be read.
      */
     protected Class defineClassFromData(File container, byte[] classData,
                                         String classname) throws IOException {
@@ -1056,6 +1081,7 @@ public class AntClassLoader extends ClassLoader implements BuildListener {
      *               Must not be <code>null</code>.
      * @param classname The name of the class in the stream.
      *                  Must not be <code>null</code>.
+     * @param container the file or directory containing the class.
      *
      * @return the Class object read from the stream.
      *
@@ -1096,6 +1122,23 @@ public class AntClassLoader extends ClassLoader implements BuildListener {
         return findClassInComponents(name);
     }
 
+    /** 
+     * Indicate if the given file is in this loader's path
+     *
+     * @param component the file which is to be checked
+     *
+     * @return true if the file is in the class path
+     */
+    protected boolean isInPath(File component) {
+        for (Enumeration e = pathComponents.elements(); e.hasMoreElements();) {
+            File pathComponent = (File) e.nextElement();
+            if (pathComponent.equals(component)) {
+                return true;
+            }
+        }
+        return false;
+    }
+    
 
     /**
      * Finds a class on the given classpath.
@@ -1121,8 +1164,8 @@ public class AntClassLoader extends ClassLoader implements BuildListener {
                 try {
                     stream = getResourceStream(pathComponent, classFilename);
                     if (stream != null) {
-                        log("Loaded from " + pathComponent + " " + classFilename,
-                                Project.MSG_DEBUG );
+                        log("Loaded from " + pathComponent + " " 
+                            + classFilename, Project.MSG_DEBUG);
                         return getClassFromStream(stream, name, pathComponent);
                     }
                 } catch (SecurityException se) {
@@ -1173,7 +1216,7 @@ public class AntClassLoader extends ClassLoader implements BuildListener {
      */
     public synchronized void cleanup() {
         for (Enumeration e = zipFiles.elements(); e.hasMoreElements();) {
-            ZipFile zipFile = (ZipFile)e.nextElement();
+            ZipFile zipFile = (ZipFile) e.nextElement();
             try {
                 zipFile.close();
             } catch (IOException ioe) {
@@ -1248,10 +1291,10 @@ public class AntClassLoader extends ClassLoader implements BuildListener {
      * here
      */
     public void addJavaLibraries() {
-        Vector packages=JavaEnvUtils.getJrePackages();
-        Enumeration e=packages.elements();
-        while(e.hasMoreElements()) {
-            String packageName=(String)e.nextElement();
+        Vector packages = JavaEnvUtils.getJrePackages();
+        Enumeration e = packages.elements();
+        while (e.hasMoreElements()) {
+            String packageName = (String) e.nextElement();
             addSystemPackageRoot(packageName);
         }
     }

src/main/org/apache/tools/ant/loader/AntClassLoader2.java

@@ -55,6 +55,9 @@ package org.apache.tools.ant.loader;
 
 import java.io.File;
 import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.Reader;
 import org.apache.tools.ant.AntClassLoader;
 import org.apache.tools.ant.Project;
 import java.util.jar.Manifest;
@@ -63,17 +66,85 @@ import java.util.jar.Attributes;
 import java.util.jar.Attributes.Name;
 import java.net.URL;
 import java.net.MalformedURLException;
+import java.util.zip.ZipEntry;
+import java.util.StringTokenizer;
+import org.apache.tools.ant.util.FileUtils;
 
+/**
+ * An implementation of the AntClassLoader suitable for use on post JDK 1.1
+ * platforms
+ *
+ * @author Conor MacNeill
+ */
 public class AntClassLoader2 extends AntClassLoader {
+    /** Instance of a utility class to use for file operations. */
+    private FileUtils fileUtils;
+    
+    /**
+     * Constructor
+     */
+    public AntClassLoader2() {
+        fileUtils = FileUtils.newFileUtils();
+    }
+    
+    /**
+     * Define a class given its bytes
+     *
+     * @param container the container from which the class data has been read
+     *                  may be a directory or a jar/zip file.
+     *
+     * @param classData the bytecode data for the class
+     * @param className the name of the class
+     *
+     * @return the Class instance created from the given data
+     *
+     * @throws IOException if the class data cannot be read.
+     */
     protected Class defineClassFromData(File container, byte[] classData,
                                         String className) throws IOException {
 
-        definePackage(container, className);                                            
+        definePackage(container, className);
         return defineClass(className, classData, 0, classData.length,
-                           Project.class.getProtectionDomain());                                             
+                           Project.class.getProtectionDomain());
                                             
     }
-    
+
+    /**
+     * Get the manifest from the given jar, if it is indeed a jar and it has a 
+     * manifest
+     *
+     * @param container the File from which a manifest is required.
+     *
+     * @return the jar's manifest or null is the container is not a jar or it
+     *         has no manifest.
+     *
+     * @exception IOException if the manifest cannot be read.
+     */
+    private Manifest getJarManifest(File container) throws IOException {
+        if (container.isDirectory()) {
+            return null;
+        }
+        JarFile jarFile = null;
+        try {
+            jarFile = new JarFile(container);
+            return jarFile.getManifest();
+        } finally {
+            if (jarFile != null) {
+                jarFile.close();
+            }
+        }
+    }
+                
+    /**
+     * Define the package information associated with a class.
+     *
+     * @param container the file containing the class definition.
+     * @param className the class name of for which the package information
+     *        is to be determined.
+     * 
+     * @exception IOException if the package information cannot be read from the
+     *            container.
+     */                
     protected void definePackage(File container, String className) 
         throws IOException {
         int classIndex = className.lastIndexOf('.');
@@ -88,27 +159,26 @@ public class AntClassLoader2 extends AntClassLoader {
         }
         
         // define the package now 
-        Manifest manifest = null;
-        if (!container.isDirectory()) {
-            JarFile jarFile = null;
-            try {
-                jarFile = new JarFile(container);
-                manifest = jarFile.getManifest();
-            } finally {
-                if (jarFile != null) {
-                    jarFile.close();
-                }
-            }
-        }
+        Manifest manifest = getJarManifest(container);
         
         if (manifest == null) {
-            definePackage(packageName, null, null, null, null, null, null, null);
+            definePackage(packageName, null, null, null, null, null, 
+                          null, null);
         } else {
             definePackage(container, packageName, manifest);
         }
     }
     
-    protected void definePackage(File container, String packageName, Manifest manifest) {
+    /**
+     * Define the package information when the class comes from a 
+     * jar with a manifest
+     *
+     * @param container the jar file containing the manifest
+     * @param packageName the name of the package being defined.
+     * @param manifest the jar's manifest
+     */
+    protected void definePackage(File container, String packageName, 
+                                 Manifest manifest) {
         String sectionName = packageName.replace('.', '/') + "/";
 
         String specificationTitle = null;
@@ -180,7 +250,73 @@ public class AntClassLoader2 extends AntClassLoader {
         
         definePackage(packageName, specificationTitle, specificationVersion, 
                       specificationVendor, implementationTitle, 
-                      implementationVersion, implementationVendor, sealBase);        
+                      implementationVersion, implementationVendor, sealBase);
+    }
+    
+    
+    /**
+     * Add a file to the path. This classloader reads the manifest, if 
+     * available, and adds any additional class path jars specified in the
+     * manifest.
+     *
+     * @param pathComponent the file which is to be added to the path for
+     *                      this class loader
+     *
+     * @throws IOException if data needed from the file cannot be read.
+     */
+    protected void addPathFile(File pathComponent) throws IOException {
+        super.addPathFile(pathComponent);
+        
+        if (pathComponent.isDirectory()) {
+            return;
+        }
+        
+        String classpath = null;
+        JarFile jarFile = null;
+        InputStream manifestStream = null;
+        try {
+            jarFile = new JarFile(pathComponent);
+            manifestStream 
+                = jarFile.getInputStream(new ZipEntry("META-INF/MANIFEST.MF"));
+
+            if (manifestStream == null) {
+                return;
+            }                
+            Reader manifestReader = new InputStreamReader(manifestStream);
+            org.apache.tools.ant.taskdefs.Manifest manifest
+                = new org.apache.tools.ant.taskdefs.Manifest(manifestReader);
+            classpath 
+                = manifest.getMainSection().getAttributeValue("Class-Path");
+               
+        } catch (org.apache.tools.ant.taskdefs.ManifestException e) {
+            // ignore
+        } finally {
+            if (manifestStream != null) {
+                manifestStream.close();
+            }
+            if (jarFile != null) {
+                jarFile.close();
+            }
+        }
+        
+        if (classpath != null) {
+            URL baseURL = fileUtils.getFileURL(pathComponent);
+            StringTokenizer st = new StringTokenizer(classpath);
+            while (st.hasMoreTokens()) {
+                String classpathElement = st.nextToken();
+                URL libraryURL = new URL(baseURL, classpathElement);
+                if (!libraryURL.getProtocol().equals("file")) {
+                    log("Skipping jar library " + classpathElement 
+                        + " since only relative URLs are supported by this"
+                        + " loader", Project.MSG_VERBOSE);
+                    continue;
+                }
+                File libraryFile = new File(libraryURL.getFile());
+                if (libraryFile.exists() && !isInPath(libraryFile)) {
+                    addPathFile(libraryFile);
+                }
+            }
+        }
     }
 }