Prior to JDK1.3, an "Optional Package" was known as an Extension. + * The specification for this mechanism is available in the JDK1.3 + * documentation in the directory + * $JDK_HOME/docs/guide/extensions/versioning.html. Alternatively it is + * available online at + * http://java.sun.com/j2se/1.3/docs/guide/extensions/versioning.html.
+ * + * @author Peter Donald + * @ant.task name="jarlib-manifest" + */ +public final class JarLibManifestTask + extends Task +{ + /** + * Version of manifest spec that task generates. + */ + private static final String MANIFEST_VERSION = "1.0"; + + /** + * "Created-By" string used when creating manifest. + */ + private static final String CREATED_BY = "Created-By"; + + /** + * The library to display information about. + */ + private File m_destfile; + + /** + * The extension supported by this library (if any). + */ + private Extension m_extension; + + /** + * ExtensionAdapter objects representing + * dependencies required by library. + */ + private final ArrayList m_dependencies = new ArrayList(); + + /** + * ExtensionAdapter objects representing optional + * dependencies required by library. + */ + private final ArrayList m_optionals = new ArrayList(); + + /** + * Extra attributes the user specifies for main section + * in manifest. + */ + private final ArrayList m_extraAttributes = new ArrayList(); + + /** + * The location where generated manifest is placed. + * + * @param destfile The location where generated manifest is placed. + */ + public void setDestfile( final File destfile ) + { + m_destfile = destfile; + } + + /** + * Adds an extension that this library implements. + * + * @param extensionAdapter an extension that this library implements. + */ + public void addConfiguredExtension( final ExtensionAdapter extensionAdapter ) + throws BuildException + { + if( null != m_extension ) + { + final String message = + "Can not have multiple extensions defined in one library."; + throw new BuildException( message ); + } + else + { + m_extension = extensionAdapter.toExtension(); + } + } + + /** + * Adds a set of extensions that this library requires. + * + * @param extensionSet a set of extensions that this library requires. + */ + public void addConfiguredDepends( final ExtensionSet extensionSet ) + { + m_dependencies.add( extensionSet ); + } + + /** + * Adds a set of extensions that this library optionally requires. + * + * @param extensionSet a set of extensions that this library optionally requires. + */ + public void addConfiguredOptions( final ExtensionSet extensionSet ) + { + m_optionals.add( extensionSet ); + } + + /** + * Adds an attribute that is to be put in main section of manifest. + * + * @param attribute an attribute that is to be put in main section of manifest. + */ + public void addConfiguredAttribute( final ExtraAttribute attribute ) + { + m_extraAttributes.add( attribute ); + } + + public void execute() + throws BuildException + { + validate(); + + final Manifest manifest = new Manifest(); + final Attributes attributes = manifest.getMainAttributes(); + + attributes.put( Attributes.Name.MANIFEST_VERSION, MANIFEST_VERSION ); + final String createdBy = "Apache Ant " + getProject().getProperty( "ant.version" ); + attributes.putValue( CREATED_BY, createdBy ); + + appendExtraAttributes( attributes ); + + if( null != m_extension ) + { + Extension.addExtension( m_extension, attributes ); + } + + //Add all the dependency data to manifest for dependencies + final ArrayList depends = toExtensions( m_dependencies ); + appendExtensionList( attributes, + Extension.EXTENSION_LIST, + "lib", + depends.size() ); + appendLibraryList( attributes, "lib", depends ); + + //Add all the dependency data to manifest for "optional" + //dependencies + final ArrayList option = toExtensions( m_optionals ); + appendExtensionList( attributes, + Extension.OPTIONAL_EXTENSION_LIST, + "opt", + option.size() ); + appendLibraryList( attributes, "opt", option ); + + try + { + final String message = "Generating manifest " + m_destfile.getAbsoluteFile(); + log( message, Project.MSG_INFO ); + writeManifest( manifest ); + } + catch( final IOException ioe ) + { + throw new BuildException( ioe.getMessage(), ioe ); + } + } + + /** + * Validate the tasks parameters. + * + * @throws BuildException if invalid parameters found + */ + private void validate() + throws BuildException + { + if( null == m_destfile ) + { + final String message = "Destfile attribute not specified."; + throw new BuildException( message ); + } + if( m_destfile.exists() && !m_destfile.isFile() ) + { + final String message = m_destfile + " is not a file."; + throw new BuildException( message ); + } + } + + /** + * Add any extra attributes to the manifest. + * + * @param attributes the manifest section to write + * attributes to + */ + private void appendExtraAttributes( final Attributes attributes ) + { + final Iterator iterator = m_extraAttributes.iterator(); + while( iterator.hasNext() ) + { + final ExtraAttribute attribute = + (ExtraAttribute)iterator.next(); + attributes.putValue( attribute.getName(), + attribute.getValue() ); + } + } + + /** + * Write out manifest to destfile. + * + * @param manifest the manifest + * @throws IOException if error writing file + */ + private void writeManifest( final Manifest manifest ) + throws IOException + { + FileOutputStream output = null; + try + { + output = new FileOutputStream( m_destfile ); + manifest.write( output ); + output.flush(); + } + finally + { + if( null != output ) + { + try + { + output.close(); + } + catch( IOException e ) + { + } + } + } + } + + /** + * Append specified extensions to specified attributes. + * Use the extensionKey to list the extensions, usually "Extension-List:" + * for required dependencies and "Optional-Extension-List:" for optional + * dependencies. NOTE: "Optional" dependencies are not part of the + * specification. + * + * @param attributes the attributes to add extensions to + * @param extensions the list of extensions + * @throws BuildException if an error occurs + */ + private void appendLibraryList( final Attributes attributes, + final String listPrefix, + final ArrayList extensions ) + throws BuildException + { + final int size = extensions.size(); + for( int i = 0; i < size; i++ ) + { + final Extension extension = (Extension)extensions.get( i ); + final String prefix = listPrefix + i + "-"; + Extension.addExtension( extension, prefix, attributes ); + } + } + + /** + * Append an attribute such as "Extension-List: lib0 lib1 lib2" + * using specified prefix and counting up to specified size. + * Also use specified extensionKey so that can generate list of + * optional dependencies aswell. + * + * @param size the number of librarys to list + * @param listPrefix the prefix for all librarys + * @param attributes the attributes to add key-value to + * @param extensionKey the key to use + */ + private void appendExtensionList( final Attributes attributes, + final Attributes.Name extensionKey, + final String listPrefix, + final int size ) + { + final StringBuffer sb = new StringBuffer(); + for( int i = 0; i < size; i++ ) + { + sb.append( listPrefix + i ); + sb.append( ' ' ); + } + + //add in something like + //"Extension-List: javahelp java3d" + attributes.put( extensionKey, sb.toString() ); + } + + /** + * Convert a list of ExtensionSet objects to extensions. + * + * @param extensionSets the list of ExtensionSets to add to list + * @throws BuildException if an error occurs + */ + private ArrayList toExtensions( final ArrayList extensionSets ) + throws BuildException + { + final ArrayList results = new ArrayList(); + + final int size = extensionSets.size(); + for( int i = 0; i < size; i++ ) + { + final ExtensionSet set = (ExtensionSet)extensionSets.get( i ); + final Extension[] extensions = set.toExtensions( getProject() ); + for( int j = 0; j < extensions.length; j++ ) + { + results.add( extensions[ j ] ); + } + } + + return results; + } +}