Moved GlueGen out of the JOGL workspace and into its own project.

Restructured JOGL and JOAL build processes to separately invoke
GlueGen's main build.xml before using it to generate their code.
Refactored OS/CPU detection code into gluegen-cpptasks.xml build file
in GlueGen workspace, which is now imported by both the JOGL and JOAL
build processes. Unfortunately it seems to be somewhat difficult to
completely factor out the C compiler configuration into the GlueGen
workspace so this has been left for a later date. Added missed
ALProcAddressLookup file to JOAL workspace. Updated JOGL and JOAL
build documentation. More documentation for the GlueGen workspace is
forthcoming.


git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/../svn-server-sync/gluegen/trunk@3 a78bb65f-1512-4460-ba86-f6dc96a7bf27

2 files changed, 797 insertions, 0 deletions

diff --git a/src/java/com/sun/gluegen/ant/GlueGenTask.java b/src/java/com/sun/gluegen/ant/GlueGenTask.java
new file mode 100644
index 0000000..b900098
--- /dev/null
+++ b/src/java/com/sun/gluegen/ant/GlueGenTask.java
@@ -0,0 +1,494 @@
+package com.sun.gluegen.ant;
+
+/*
+ * GlueGenTask.java
+ * Copyright (C) 2003 Rob Grzywinski ([email protected])
+ *
+ * Copying, distribution and use of this software in source and binary
+ * forms, with or without modification, is permitted provided that the
+ * following conditions are met:
+ *
+ * Distributions of source code must reproduce the copyright notice,
+ * this list of conditions and the following disclaimer in the source
+ * code header files; and Distributions of binary code must reproduce
+ * the copyright notice, this list of conditions and the following
+ * disclaimer in the documentation, Read me file, license file and/or
+ * other materials provided with the software distribution.
+ *
+ * The names of Sun Microsystems, Inc. ("Sun") and/or the copyright
+ * holder may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS," WITHOUT A WARRANTY OF ANY
+ * KIND. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
+ * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, NON-INTERFERENCE, ACCURACY OF
+ * INFORMATIONAL CONTENT OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. THE
+ * COPYRIGHT HOLDER, SUN AND SUN'S LICENSORS SHALL NOT BE LIABLE FOR
+ * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
+ * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL THE
+ * COPYRIGHT HOLDER, SUN OR SUN'S LICENSORS BE LIABLE FOR ANY LOST
+ * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL,
+ * CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND
+ * REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF OR
+ * INABILITY TO USE THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGES. YOU ACKNOWLEDGE THAT THIS SOFTWARE IS NOT
+ * DESIGNED, LICENSED OR INTENDED FOR USE IN THE DESIGN, CONSTRUCTION,
+ * OPERATION OR MAINTENANCE OF ANY NUCLEAR FACILITY. THE COPYRIGHT
+ * HOLDER, SUN AND SUN'S LICENSORS DISCLAIM ANY EXPRESS OR IMPLIED
+ * WARRANTY OF FITNESS FOR SUCH USES.
+ */
+
+import java.io.IOException;
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+
+import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.DirectoryScanner;
+import org.apache.tools.ant.Project;
+import org.apache.tools.ant.Task;
+import org.apache.tools.ant.taskdefs.Execute;
+import org.apache.tools.ant.taskdefs.LogStreamHandler;
+import org.apache.tools.ant.types.CommandlineJava;
+import org.apache.tools.ant.types.DirSet;
+import org.apache.tools.ant.types.FileSet;
+import org.apache.tools.ant.types.Path;
+import org.apache.tools.ant.types.PatternSet;
+import org.apache.tools.ant.types.Reference;
+import org.apache.tools.ant.util.JavaEnvUtils;
+
+/**
+ * <p>An <a href="http://ant.apache.org">ANT</a> {@link org.apache.tools.ant.Task}
+ * for using {@link com.sun.gluegen.GlueGen}.</p>
+ * 
+ * <p>Usage:</p>
+ * <pre>
+    &lt;gluegen src="[source C file]" 
+                includes="[optional directory pattern of include files to include]"
+                excludes="[optional directory pattern of include files to exclude]"
+                includeRefid="[optional FileSet or DirSet for include files]"
+                literalInclude="[optional hack to get around FileSet / DirSet issues with different drives]"
+                emitter="[emitter class name]"
+                config="[configuration file]" /&gt;
+ * </pre> 
+ *
+ * @author Rob Grzywinski <a href="mailto:[email protected]">[email protected]</a>
+ */
+// FIXME:  blow out javadoc
+// NOTE:  this has not been exhaustively tested
+public class GlueGenTask extends Task
+{
+    /**
+     * <p>The {@link com.sun.gluegen.GlueGen} classname.</p>
+     */
+    private static final String GLUE_GEN = "com.sun.gluegen.GlueGen";
+    
+    // =========================================================================
+    /**
+     * <p>The {@link org.apache.tools.ant.types.CommandlineJava} that is used
+     * to execute {@link com.sun.gluegen.GlueGen}.</p>
+     */
+    private CommandlineJava gluegenCommandline;
+
+    // =========================================================================
+    /**
+     * <p>The name of the emitter class.</p>
+     */
+    private String emitter;
+
+    /**
+     * <p>The configuration file name.</p>
+     */
+    private String configuration;
+    
+    /**
+     * <p>The name of the source C file that is to be parsed.</p>
+     */
+    private String sourceFile;
+    
+    /**
+     * <p>The {@link org.apache.tools.ant.types.FileSet} of includes.</p>
+     */
+    private FileSet includeSet = new FileSet();
+    
+    /**
+     * <p>Because a {@link org.apache.tools.ant.types.FileSet} will include
+     * everything in its base directory if it is left untouched, the <code>includeSet</code>
+     * must only be added to the set of includes if it has been <i>explicitly</i>
+     * set.</p>
+     */
+    private boolean usedIncludeSet = false; // by default it is not used 
+    
+    /**
+     * <p>The set of include sets.  This allows includes to be added in multiple
+     * fashions.</p>
+     */
+    // FIXME:  rename to listXXXX
+    private List setOfIncludeSets = new LinkedList();
+
+    /**
+     * <p>A single literal directory to include.  This is to get around the
+     * fact that neither {@link org.apache.tools.ant.types.FileSet} nor
+     * {@link org.apache.tools.ant.types.DirSet} can handle multiple drives in
+     * a sane manner.  If <code>null</code> then it has not been specified.</p>
+     */
+    private String literalInclude;
+    
+    // =========================================================================
+    /**
+     * <p>Create and add the VM and classname to {@link org.apache.tools.ant.types.CommandlineJava}.</p>
+     */
+    public GlueGenTask()
+    {
+        // create the CommandlineJava that will be used to call GlueGen
+        gluegenCommandline = new CommandlineJava();
+        
+        // set the VM and classname in the commandline
+        gluegenCommandline.setVm(JavaEnvUtils.getJreExecutable("java"));
+        gluegenCommandline.setClassname(GLUE_GEN);
+        // gluegenCommandline.createVmArgument().setValue("-verbose:class");
+    }
+
+    // =========================================================================
+    // ANT getters and setters
+    /**
+     * <p>Set the emitter class name.  This is called by ANT.</p>
+     * 
+     * @param  emitter the name of the emitter class
+     */
+    public void setEmitter(String emitter)
+    {
+        log( ("Setting emitter class name to: " + emitter), Project.MSG_VERBOSE);
+        this.emitter = emitter;
+    }
+
+    /**
+     * <p>Set the configuration file name.  This is called by ANT.</p>
+     * 
+     * @param  configuration the name of the configuration file
+     */
+    public void setConfig(String configuration)
+    {
+        log( ("Setting configuration file name to: " + configuration), 
+              Project.MSG_VERBOSE);
+        this.configuration = configuration;
+    }
+
+    /**
+     * <p>Set the source C file that is to be parsed.  This is called by ANT.</p>
+     * 
+     * @param  sourceFile the name of the source file
+     */
+    public void setSrc(String sourceFile)
+    {
+        log( ("Setting source file name to: " + sourceFile), Project.MSG_VERBOSE);
+        this.sourceFile = sourceFile;
+    }
+
+    /**
+     * <p>Set a single literal include directory.  See the <code>literalInclude</code>
+     * javadoc for more information.</p>
+     * 
+     * @param  directory the directory to include
+     */
+    public void setLiteralInclude(String directory)
+    {
+        this.literalInclude = directory;
+    }
+
+    /**
+     * <p>Add an include file to the list.  This is called by ANT for a nested
+     * element.</p>
+     * 
+     * @return {@link org.apache.tools.ant.types.PatternSet.NameEntry}
+     */
+    public PatternSet.NameEntry createInclude()
+    {
+        usedIncludeSet = true;
+        return includeSet.createInclude();
+    }
+
+    /**
+     * <p>Add an include file to the list.  This is called by ANT for a nested
+     * element.</p>
+     * 
+     * @return {@link org.apache.tools.ant.types.PatternSet.NameEntry}
+     */
+    public PatternSet.NameEntry createIncludesFile()
+    {
+        usedIncludeSet = true;
+        return includeSet.createIncludesFile();
+    }
+
+    /**
+     * <p>Set the set of include patterns.  Patterns may be separated by a comma
+     * or a space.  This is called by ANT.</p>
+     *
+     * @param  includes the string containing the include patterns
+     */
+    public void setIncludes(String includes)
+    {
+        usedIncludeSet = true;
+        includeSet.setIncludes(includes);
+    }
+
+    /**
+     * <p>Add an include file to the list that is to be exluded.  This is called 
+     * by ANT for a nested element.</p>
+     * 
+     * @return {@link org.apache.tools.ant.types.PatternSet.NameEntry}
+     */
+    public PatternSet.NameEntry createExclude()
+    {
+        usedIncludeSet = true;
+        return includeSet.createExclude();
+    }
+
+    /**
+     * <p>Add an exclude file to the list.  This is called by ANT for a nested
+     * element.</p>
+     * 
+     * @return {@link org.apache.tools.ant.types.PatternSet.NameEntry}
+     */
+    public PatternSet.NameEntry createExcludesFile()
+    {
+        usedIncludeSet = true;
+        return includeSet.createExcludesFile();
+    }
+
+    /**
+     * <p>Set the set of exclude patterns.  Patterns may be separated by a comma
+     * or a space.  This is called by ANT.</p>
+     *
+     * @param  includes the string containing the exclude patterns
+     */
+    public void setExcludes(String excludes)
+    {
+        usedIncludeSet = true;
+        includeSet.setExcludes(excludes);
+    }
+
+    /**
+     * <p>Set a {@link org.apache.tools.ant.types.Reference} to simplify adding
+     * of complex sets of files to include.  This is called by ANT.</p>?
+     * 
+     * @param  reference a <code>Reference</code> to a {@link org.apache.tools.ant.types.FileSet}
+     *         or {@link org.apache.tools.ant.types.DirSet}
+     * @throws BuildException if the specified <code>Reference</code> is not
+     *         either a <code>FileSet</code> or <code>DirSet</code>
+     */
+    public void setIncludeRefid(Reference reference) 
+    {
+        // ensure that the referenced object is either a FileSet or DirSet
+        final Object referencedObject = reference.getReferencedObject(getProject());
+        if( !( (referencedObject instanceof FileSet) || 
+               (referencedObject instanceof DirSet)) )
+        {               
+            throw new BuildException("Only FileSets or DirSets are allowed as an include refid.");
+        }
+
+        // add the referenced object to the set of include sets
+        setOfIncludeSets.add(referencedObject); 
+    }
+
+    /**
+     * <p>Add a nested {@link org.apache.tools.ant.types.DirSet} to specify
+     * the files to include.  This is called by ANT.</p>
+     * 
+     * @param  dirset the <code>DirSet</code> to be added
+     */
+    public void addDirset(DirSet dirset)
+    {
+        setOfIncludeSets.add(dirset);
+    }
+
+    /**
+     * <p>Add an optional classpath that defines the location of {@link com.sun.gluegen.GlueGen}
+     * and <code>GlueGen</code>'s dependencies.</p>
+     * 
+     * @returns {@link org.apache.tools.ant.types.Path}
+     */
+     public Path createClasspath()
+     {
+         return gluegenCommandline.createClasspath(project).createPath();
+     }
+
+    // =========================================================================
+    /**
+     * <p>Run the task.  This involves validating the set attributes, creating
+     * the command line to be executed and finally executing the command.</p>
+     * 
+     * @see  org.apache.tools.ant.Task#execute()
+     */
+    public void execute() 
+        throws BuildException 
+    {
+        // validate that all of the required attributes have been set
+        validateAttributes();
+        
+        // TODO:  add logic to determine if the generated file needs to be
+        //        regenerated
+        
+        // add the attributes to the CommandlineJava
+        addAttributes();
+
+        log(gluegenCommandline.describeCommand(), Project.MSG_VERBOSE);
+        
+        // execute the command and throw on error
+        final int error = execute(gluegenCommandline.getCommandline());
+        if(error == 1)
+            throw new BuildException( ("GlueGen returned: " + error), location);
+    }
+
+    /**
+     * <p>Ensure that the user specified all required arguments.</p>
+     * 
+     * @throws BuildException if there are required arguments that are not 
+     *         present or not valid
+     */
+    private void validateAttributes() 
+        throws BuildException
+    {
+        // validate that the emitter class is set
+        if(!isValid(emitter))
+            throw new BuildException("Invalid emitter class name: " + emitter);
+
+        // validate that the configuration file is set
+        if(!isValid(configuration))
+            throw new BuildException("Invalid configuration file name: " + configuration);
+            
+        // validate that the source file is set
+        if(!isValid(sourceFile))
+            throw new BuildException("Invalid source file name: " + sourceFile);
+            
+        // CHECK:  do there need to be includes to be valid?
+    }
+
+    /**
+     * <p>Is the specified string valid?  A valid string is non-<code>null</code>
+     * and has a non-zero length.</p>
+     * 
+     * @param  string the string to be tested for validity
+     * @return <code>true</code> if the string is valid.  <code>false</code>
+     *         otherwise. 
+     */
+    private boolean isValid(String string)
+    {
+        // check for null
+        if(string == null)
+            return false;
+            
+        // ensure that the string has a non-zero length
+        // NOTE:  must trim() to remove leading and trailing whitespace
+        if(string.trim().length() < 1)
+            return false;
+            
+        // the string is valid
+        return true;
+    }
+
+    /**
+     * <p>Add all of the attributes to the command line.  They have already
+     * been validated.</p>
+     */
+    private void addAttributes()
+        throws BuildException
+    {
+        // NOTE:  GlueGen uses concatenated flag / value rather than two 
+        //        separate arguments
+        
+        // add the emitter class name
+        gluegenCommandline.createArgument().setValue("-E" + emitter);
+        
+        // add the configuration file name
+        gluegenCommandline.createArgument().setValue("-C" + configuration);
+        
+        // add the includedSet to the setOfIncludeSets to simplify processing
+        // all types of include sets ONLY if it has been set.
+        // NOTE:  see the usedIncludeSet member javadoc for more info 
+        // NOTE:  references and nested DirSets have already been added to the
+        //        set of include sets
+        if(usedIncludeSet)
+        {
+            includeSet.setDir(getProject().getBaseDir()); // NOTE:  the base dir must be set
+            setOfIncludeSets.add(includeSet);
+        }
+        
+        // iterate over all include sets and add their directories to the 
+        // list of included directories.
+        final List includedDirectories = new LinkedList();
+        for(Iterator includes=setOfIncludeSets.iterator(); includes.hasNext(); )
+        {
+            // get the included set and based on its type add the directories
+            // to includedDirectories
+        	Object include = (Object)includes.next();
+            final String[] directoryDirs;
+            if(include instanceof FileSet)
+            {
+                final FileSet fileSet = (FileSet)include;
+                DirectoryScanner directoryScanner = fileSet.getDirectoryScanner(getProject());
+                directoryDirs = directoryScanner.getIncludedDirectories();
+            } else if(include instanceof DirSet)
+            {
+                final DirSet dirSet = (DirSet)include;
+                DirectoryScanner directoryScanner = dirSet.getDirectoryScanner(getProject());
+                directoryDirs = directoryScanner.getIncludedDirectories();
+            } else 
+            {
+                // NOTE:  this cannot occur as it is checked on setXXX() but
+                //        just to be pedantic this is here
+                throw new BuildException("Invalid included construct."); 
+            }
+        	
+            // add the directoryDirs to the includedDirectories
+            // TODO:  exclude any directory that is already in the list
+            for(int i=0; i<directoryDirs.length; i++)
+            {
+            	includedDirectories.add(directoryDirs[i]);
+            }
+        }
+        
+        // if literalInclude is valid then add it to the list of included
+        // directories
+        if(isValid(literalInclude))
+            includedDirectories.add(literalInclude); 
+        
+        // add the included directories to the command
+        for(Iterator includes=includedDirectories.iterator(); includes.hasNext(); )
+        {
+        	String directory = (String)includes.next();
+            gluegenCommandline.createArgument().setValue("-I" + directory);
+        }
+
+        // finally, add the source file
+        gluegenCommandline.createArgument().setValue(sourceFile);
+    }
+
+    /** 
+     * <p>Execute {@link com.sun.gluegen.GlueGen} in a forked JVM.</p>
+     * 
+     * @throws BuildException
+     */
+    private int execute(String[] command) 
+        throws BuildException
+    {
+        // create the object that will perform the command execution
+        Execute execute = new Execute(new LogStreamHandler(this, Project.MSG_INFO,
+                                                           Project.MSG_WARN), 
+                                      null);
+                                      
+        // set the project and command line
+        execute.setAntRun(project);
+        execute.setCommandline(command);
+        
+        // execute the command
+        try
+        {
+            return execute.execute();
+        } catch(IOException ioe)
+        {
+            throw new BuildException(ioe, location);
+        }
+    }
+}
diff --git a/src/java/com/sun/gluegen/ant/StaticGLGenTask.java b/src/java/com/sun/gluegen/ant/StaticGLGenTask.java
new file mode 100644
index 0000000..255ab8a
--- /dev/null
+++ b/src/java/com/sun/gluegen/ant/StaticGLGenTask.java
@@ -0,0 +1,303 @@
+package com.sun.gluegen.ant;
+
+/*
+ * StaticGLGenTask.java
+ * Copyright (C) 2003 Rob Grzywinski ([email protected])
+ *
+ * Copying, distribution and use of this software in source and binary
+ * forms, with or without modification, is permitted provided that the
+ * following conditions are met:
+ *
+ * Distributions of source code must reproduce the copyright notice,
+ * this list of conditions and the following disclaimer in the source
+ * code header files; and Distributions of binary code must reproduce
+ * the copyright notice, this list of conditions and the following
+ * disclaimer in the documentation, Read me file, license file and/or
+ * other materials provided with the software distribution.
+ *
+ * The names of Sun Microsystems, Inc. ("Sun") and/or the copyright
+ * holder may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS," WITHOUT A WARRANTY OF ANY
+ * KIND. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
+ * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, NON-INTERFERENCE, ACCURACY OF
+ * INFORMATIONAL CONTENT OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. THE
+ * COPYRIGHT HOLDER, SUN AND SUN'S LICENSORS SHALL NOT BE LIABLE FOR
+ * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
+ * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL THE
+ * COPYRIGHT HOLDER, SUN OR SUN'S LICENSORS BE LIABLE FOR ANY LOST
+ * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL,
+ * CONSEQUENTIAL, INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND
+ * REGARDLESS OF THE THEORY OF LIABILITY, ARISING OUT OF THE USE OF OR
+ * INABILITY TO USE THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGES. YOU ACKNOWLEDGE THAT THIS SOFTWARE IS NOT
+ * DESIGNED, LICENSED OR INTENDED FOR USE IN THE DESIGN, CONSTRUCTION,
+ * OPERATION OR MAINTENANCE OF ANY NUCLEAR FACILITY. THE COPYRIGHT
+ * HOLDER, SUN AND SUN'S LICENSORS DISCLAIM ANY EXPRESS OR IMPLIED
+ * WARRANTY OF FITNESS FOR SUCH USES.
+ */
+
+import java.io.IOException;
+
+import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.DirectoryScanner;
+import org.apache.tools.ant.Project;
+import org.apache.tools.ant.Task;
+import org.apache.tools.ant.taskdefs.Execute;
+import org.apache.tools.ant.taskdefs.LogStreamHandler;
+import org.apache.tools.ant.types.CommandlineJava;
+import org.apache.tools.ant.types.FileSet;
+import org.apache.tools.ant.types.Path;
+import org.apache.tools.ant.types.PatternSet;
+import org.apache.tools.ant.util.JavaEnvUtils;
+
+/**
+ * <p>An <a href="http://ant.apache.org">ANT</a> {@link org.apache.tools.ant.Task}
+ * for using {@link com.sun.gluegen.opengl.BuildStaticGLInfo}.</p>
+ * 
+ * <p>Usage:</p>
+ * <pre>
+    &lt;staticglgen package="[generated files package]" 
+                    headers="[file pattern of GL headers]"
+                    outputdir="[directory to output the generated files]" /&gt;
+ * </pre> 
+ *
+ * @author Rob Grzywinski <a href="mailto:[email protected]">[email protected]</a>
+ */
+// FIXME:  blow out javadoc
+public class StaticGLGenTask extends Task
+{
+    /**
+     * <p>The {@link com.sun.gluegen.opengl.BuildStaticGLInfo} classname.</p>
+     */
+    private static final String GL_GEN = "com.sun.gluegen.opengl.BuildStaticGLInfo";
+    
+    // =========================================================================
+    /**
+     * <p>The {@link org.apache.tools.ant.types.CommandlineJava} that is used
+     * to execute {@link com.sun.gluegen.opengl.BuildStaticGLInfo}.</p>
+     */
+    private CommandlineJava glgenCommandline;
+
+    // =========================================================================
+    /**
+     * <p>The package name for the generated files.</p>
+     */
+    private String packageName;
+
+    /**
+     * <p>The output directory.</p>
+     */
+    private String outputDirectory;
+    
+    /**
+     * <p>The {@link org.apache.tools.ant.types.FileSet} of GL headers.</p>
+     */
+    private FileSet headerSet = new FileSet();
+    
+    // =========================================================================
+    /**
+     * <p>Create and add the VM and classname to {@link org.apache.tools.ant.types.CommandlineJava}.</p>
+     */
+    public StaticGLGenTask()
+    {
+        // create the CommandlineJava that will be used to call BuildStaticGLInfo
+        glgenCommandline = new CommandlineJava();
+        
+        // set the VM and classname in the commandline
+        glgenCommandline.setVm(JavaEnvUtils.getJreExecutable("java"));
+        glgenCommandline.setClassname(GL_GEN);
+    }
+
+    // =========================================================================
+    // ANT getters and setters
+    /**
+     * <p>Set the package name for the generated files.  This is called by ANT.</p>
+     * 
+     * @param  packageName the name of the package for the generated files
+     */
+    public void setPackage(String packageName)
+    {
+        log( ("Setting package name to: " + packageName), Project.MSG_VERBOSE);
+        this.packageName = packageName;
+    }
+
+    /**
+     * <p>Set the output directory.  This is called by ANT.</p>
+     * 
+     * @param  directory the output directory
+     */
+    public void setOutputDir(String directory)
+    {
+        log( ("Setting output directory to: " + directory), 
+              Project.MSG_VERBOSE);
+        this.outputDirectory = directory;
+    }
+
+    /**
+     * <p>Add a header file to the list.  This is called by ANT for a nested
+     * element.</p>
+     * 
+     * @return {@link org.apache.tools.ant.types.PatternSet.NameEntry}
+     */
+    public PatternSet.NameEntry createHeader()
+    {
+        return headerSet.createInclude();
+    }
+
+    /**
+     * <p>Add a header file to the list.  This is called by ANT for a nested
+     * element.</p>
+     * 
+     * @return {@link org.apache.tools.ant.types.PatternSet.NameEntry}
+     */
+    public PatternSet.NameEntry createHeadersFile()
+    {
+        return headerSet.createIncludesFile();
+    }
+
+    /**
+     * <p>Set the set of header patterns.  Patterns may be separated by a comma
+     * or a space.  This is called by ANT.</p>
+     *
+     * @param  headers the string containing the header patterns
+     */
+    public void setHeaders(String headers)
+    {
+        headerSet.setIncludes(headers);
+    }
+
+    /**
+     * <p>Add an optional classpath that defines the location of {@link com.sun.gluegen.opengl.BuildStaticGLInfo}
+     * and <code>BuildStaticGLInfo</code>'s dependencies.</p>
+     * 
+     * @returns {@link org.apache.tools.ant.types.Path}
+     */
+     public Path createClasspath()
+     {
+         return glgenCommandline.createClasspath(project).createPath();
+     }
+
+    // =========================================================================
+    /**
+     * <p>Run the task.  This involves validating the set attributes, creating
+     * the command line to be executed and finally executing the command.</p>
+     * 
+     * @see  org.apache.tools.ant.Task#execute()
+     */
+    public void execute() 
+        throws BuildException 
+    {
+        // validate that all of the required attributes have been set
+        validateAttributes();
+        
+        // TODO:  add logic to determine if the generated file needs to be
+        //        regenerated
+        
+        // add the attributes to the CommandlineJava
+        addAttributes();
+
+        log(glgenCommandline.describeCommand(), Project.MSG_VERBOSE);
+        
+        // execute the command and throw on error
+        final int error = execute(glgenCommandline.getCommandline());
+        if(error == 1)
+            throw new BuildException( ("BuildStaticGLInfo returned: " + error), location);
+    }
+
+    /**
+     * <p>Ensure that the user specified all required arguments.</p>
+     * 
+     * @throws BuildException if there are required arguments that are not 
+     *         present or not valid
+     */
+    private void validateAttributes() 
+        throws BuildException
+    {
+        // validate that the package name is set
+        if(!isValid(packageName))
+            throw new BuildException("Invalid package name: " + packageName);
+
+        // validate that the output directory is set
+        // TODO:  switch to file and ensure that it exists
+        if(!isValid(outputDirectory))
+            throw new BuildException("Invalid output directory name: " + outputDirectory);
+            
+        // TODO:  validate that there are headers set
+    }
+
+    /**
+     * <p>Is the specified string valid?  A valid string is non-<code>null</code>
+     * and has a non-zero length.</p>
+     * 
+     * @param  string the string to be tested for validity
+     * @return <code>true</code> if the string is valid.  <code>false</code>
+     *         otherwise. 
+     */
+    private boolean isValid(String string)
+    {
+        // check for null
+        if(string == null)
+            return false;
+            
+        // ensure that the string has a non-zero length
+        // NOTE:  must trim() to remove leading and trailing whitespace
+        if(string.trim().length() < 1)
+            return false;
+            
+        // the string is valid
+        return true;
+    }
+
+    /**
+     * <p>Add all of the attributes to the command line.  They have already
+     * been validated.</p>
+     */
+    private void addAttributes()
+    {
+        // add the package name
+        glgenCommandline.createArgument().setValue(packageName);
+        
+        // add the output directory name
+        glgenCommandline.createArgument().setValue(outputDirectory);
+        
+        // add the header -files- from the FileSet
+        headerSet.setDir(getProject().getBaseDir());
+        DirectoryScanner directoryScanner = headerSet.getDirectoryScanner(getProject());
+        String[] directoryFiles = directoryScanner.getIncludedFiles();
+        for(int i=0; i<directoryFiles.length; i++)
+        {
+            glgenCommandline.createArgument().setValue(directoryFiles[i]);
+        }
+    }
+
+    /** 
+     * <p>Execute {@link com.sun.gluegen.opengl.BuildStaticGLInfo} in a 
+     * forked JVM.</p>
+     * 
+     * @throws BuildException
+     */
+    private int execute(String[] command) 
+        throws BuildException
+    {
+        // create the object that will perform the command execution
+        Execute execute = new Execute(new LogStreamHandler(this, Project.MSG_INFO,
+                                                           Project.MSG_WARN), 
+                                      null);
+                                      
+        // set the project and command line
+        execute.setAntRun(project);
+        execute.setCommandline(command);
+        
+        // execute the command
+        try
+        {
+            return execute.execute();
+        } catch(IOException ioe)
+        {
+            throw new BuildException(ioe, location);
+        }
+    }
+}