Examples with MemoryJavaFileObject org.apache.struts2.compiler.MemoryJavaFileObject used on opensource projects

Example 1 with MemoryJavaFileObject

use of org.apache.struts2.compiler.MemoryJavaFileObject in project struts by apache.

the class JSPLoader method compileJava.

/**
 * Compiles the given source code into java bytecode
 */
private void compileJava(String className, final String source, Set<String> extraClassPath) throws IOException {
    LOG.trace("Compiling [{}], source: [{}]", className, source);
    JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
    DiagnosticCollector<JavaFileObject> diagnostics = new DiagnosticCollector<JavaFileObject>();
    // the generated bytecode is fed to the class loader
    JavaFileManager jfm = new ForwardingJavaFileManager<StandardJavaFileManager>(compiler.getStandardFileManager(diagnostics, null, null)) {

        @Override
        public JavaFileObject getJavaFileForOutput(Location location, String name, JavaFileObject.Kind kind, FileObject sibling) throws IOException {
            MemoryJavaFileObject fileObject = new MemoryJavaFileObject(name, kind);
            classLoader.addMemoryJavaFileObject(name, fileObject);
            return fileObject;
        }
    };
    // read java source code from memory
    String fileName = className.replace('.', '/') + ".java";
    SimpleJavaFileObject sourceCodeObject = new SimpleJavaFileObject(toURI(fileName), JavaFileObject.Kind.SOURCE) {

        @Override
        public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException, IllegalStateException, UnsupportedOperationException {
            return source;
        }
    };
    // build classpath
    // some entries will be added multiple times, hence the set
    List<String> optionList = new ArrayList<String>();
    Set<String> classPath = new HashSet<String>();
    // find available jars
    ClassLoaderInterface classLoaderInterface = getClassLoaderInterface();
    UrlSet urlSet = new UrlSet(classLoaderInterface);
    // find jars
    List<URL> urls = urlSet.getUrls();
    if (urls != null && urls.size() > 0) {
        final FileManagerFactory fileManagerFactoryGetInstance = ServletActionContext.getActionContext().getInstance(FileManagerFactory.class);
        final FileManagerFactory contextFileManagerFactory = (fileManagerFactoryGetInstance != null ? fileManagerFactoryGetInstance : (FileManagerFactory) ServletActionContext.getActionContext().get(StrutsConstants.STRUTS_FILE_MANAGER_FACTORY));
        final FileManagerFactory fileManagerFactory = (contextFileManagerFactory != null ? contextFileManagerFactory : new DefaultFileManagerFactory());
        final FileManager fileManagerGetInstance = fileManagerFactory.getFileManager();
        final FileManager contextFileManager = (fileManagerGetInstance != null ? fileManagerGetInstance : (FileManager) ServletActionContext.getActionContext().get(StrutsConstants.STRUTS_FILE_MANAGER));
        final FileManager fileManager = (contextFileManager != null ? contextFileManager : new DefaultFileManager());
        for (URL url : urls) {
            URL normalizedUrl = fileManager.normalizeToFileProtocol(url);
            File file = FileUtils.toFile(ObjectUtils.defaultIfNull(normalizedUrl, url));
            if (file.exists())
                classPath.add(file.getAbsolutePath());
        }
    }
    // these should be in the list already, but I am feeling paranoid
    // this jar
    classPath.add(getJarUrl(EmbeddedJSPResult.class));
    // servlet api
    classPath.add(getJarUrl(Servlet.class));
    // jsp api
    classPath.add(getJarUrl(JspPage.class));
    try {
        Class instanceManager = Class.forName("org.apache.tomcat.InstanceManager");
        classPath.add(getJarUrl(instanceManager));
    } catch (ClassNotFoundException e) {
    // ok ignore
    }
    // add extra classpath entries (jars where tlds were found will be here)
    for (Iterator<String> iterator = extraClassPath.iterator(); iterator.hasNext(); ) {
        String entry = iterator.next();
        classPath.add(entry);
    }
    String classPathString = StringUtils.join(classPath, File.pathSeparator);
    if (LOG.isDebugEnabled()) {
        LOG.debug("Compiling [#0] with classpath [#1]", className, classPathString);
    }
    optionList.addAll(Arrays.asList("-classpath", classPathString));
    // compile
    JavaCompiler.CompilationTask task = compiler.getTask(null, jfm, diagnostics, optionList, null, Arrays.asList(sourceCodeObject));
    if (!task.call()) {
        throw new StrutsException("Compilation failed:" + diagnostics.getDiagnostics().get(0).toString());
    }
}