Apache CXF example source code file (Compiler.java)

This example Apache CXF source code file (Compiler.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Apache CXF tags/keywords

arraylist, compiler, file, file, io, ioexception, ioexception, list, object, object, printwriter, streamprinter, string, string, stringbuilder, util

The Apache CXF Compiler.java source code

/**
 * 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.
 */

package org.apache.cxf.common.util;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.Writer;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Locale;

import org.apache.cxf.helpers.FileUtils;

public class Compiler {
    private long maxMemory = Runtime.getRuntime().maxMemory();
    private boolean verbose;
    private String target;
    private String outputDir;
    private String classPath;
    private boolean forceFork = Boolean.getBoolean(Compiler.class.getName() + "-fork");
    
    public Compiler() {
    }
    
    public void setMaxMemory(long l) {
        maxMemory = l;
    }
    public void setVerbose(boolean b) {
        verbose = b;
    }
    public void setTarget(String s) {
        target = s;
    }
    public void setOutputDir(File s) {
        if (s != null) {
            outputDir = s.getAbsolutePath().replace(File.pathSeparatorChar, '/');
        } else {
            outputDir = null;
        }
    }
    public void setOutputDir(String s) {
        outputDir = s.replace(File.pathSeparatorChar, '/');
    }
    public void setClassPath(String s) {
        classPath = StringUtils.isEmpty(s) ? null : s;
    }
    
    private void addArgs(List<String> list) {
        if (verbose) {
            list.add("-verbose");
        }
        if (!StringUtils.isEmpty(target)) {
            list.add("-target");
            list.add(target);
        }

        if (!StringUtils.isEmpty(outputDir)) {
            list.add("-d");
            list.add(outputDir);
        }
        
        if (StringUtils.isEmpty(classPath)) {
            String javaClasspath = System.getProperty("java.class.path");
            boolean classpathSetted = javaClasspath != null ? true : false;
            if (!classpathSetted) {
                File f = new File(getClass().getClassLoader().getResource(".").getFile());
                f = new File(f, "../lib");
                if (f.exists() && f.isDirectory()) {
                    list.add("-extdirs");
                    list.add(f.toString());                    
                }
            } else {
                list.add("-classpath");
                list.add(javaClasspath);
            }
        } else {
            list.add("-classpath");
            list.add(classPath);
        }

    }
    
    public boolean compileFiles(String[] files) {
        String endorsed = System.getProperty("java.endorsed.dirs");
        if (!forceFork) {
            try { 
                Class.forName("javax.tools.JavaCompiler");
                return useJava6Compiler(files);
            } catch (Exception ex) {
                //ignore - fork javac
            }
        }
        
        List<String> list = new ArrayList();

        // Start of honoring java.home for used javac
        String fsep = System.getProperty("file.separator");
        String javacstr = "javac";
        String platformjavacname = "javac";

        if (System.getProperty("os.name").toLowerCase().indexOf("windows") > -1) {
            platformjavacname = "javac.exe";
        }

        if (new File(System.getProperty("java.home") + fsep + platformjavacname).exists()) {
            // check if java.home is jdk home
            javacstr = System.getProperty("java.home") + fsep + platformjavacname;
        } else if (new File(System.getProperty("java.home") + fsep + ".." + fsep + "bin" + fsep
                            + platformjavacname).exists()) {
            // check if java.home is jre home
            javacstr = System.getProperty("java.home") + fsep + ".." + fsep + "bin" + fsep
                       + platformjavacname;
        }

        list.add(javacstr);
        // End of honoring java.home for used javac

        if (!StringUtils.isEmpty(endorsed)) {
            list.add("-endorseddirs");
            list.add(endorsed);
        }

        //fix for CXF-2081, set maximum heap of this VM to javac.
        list.add("-J-Xmx" + maxMemory);

        addArgs(list);
        
        int idx = list.size();
        list.addAll(Arrays.asList(files));

        return internalCompile(list.toArray(new String[list.size()]), idx);
    }

    private boolean useJava6Compiler(String[] files) 
        throws Exception {
        
        Object compiler = Class.forName("javax.tools.ToolProvider")
            .getMethod("getSystemJavaCompiler").invoke(null);
        Object fileManager = compiler.getClass().getMethod("getStandardFileManager", 
                                                           Class.forName("javax.tools.DiagnosticListener"),
                                                           Locale.class,
                                                           Charset.class).invoke(compiler, null, null, null);
        Object fileList = fileManager.getClass().getMethod("getJavaFileObjectsFromStrings", Iterable.class)
            .invoke(fileManager, Arrays.asList(files));
        
        
        List<String> args = new ArrayList();
        addArgs(args);
        Object task = compiler.getClass().getMethod("getTask", 
                                                    Writer.class,
                                                    Class.forName("javax.tools.JavaFileManager"),
                                                    Class.forName("javax.tools.DiagnosticListener"),
                                                    Iterable.class,
                                                    Iterable.class,
                                                    Iterable.class)
                                                    .invoke(compiler, null, fileManager, null, 
                                                            args, null, fileList);
        Boolean ret = (Boolean)task.getClass().getMethod("call").invoke(task);
        fileManager.getClass().getMethod("close").invoke(fileManager);
        return ret;
    }

    public boolean internalCompile(String[] args, int sourceFileIndex) {
        Process p = null;
        String cmdArray[] = null;
        File tmpFile = null;
        try {
            if (isLongCommandLines(args) && sourceFileIndex >= 0) {
                PrintWriter out = null;
                tmpFile = FileUtils.createTempFile("cxf-compiler", null);
                out = new PrintWriter(new FileWriter(tmpFile));
                for (int i = sourceFileIndex; i < args.length; i++) {
                    if (args[i].indexOf(" ") > -1) {
                        args[i] = args[i].replace(File.separatorChar, '/');
                        //
                        // javac gives an error if you use forward slashes
                        // with package-info.java. Refer to:
                        // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6198196
                        //
                        if (args[i].indexOf("package-info.java") > -1
                            && System.getProperty("os.name").toLowerCase().indexOf("windows") > -1) {
                            out.println("\"" + args[i].replaceAll("/", "\\\\\\\\") + "\"");
                        } else {
                            out.println("\"" + args[i] + "\"");
                        }
                    } else {
                        out.println(args[i]);
                    }
                }
                out.flush();
                out.close();
                cmdArray = new String[sourceFileIndex + 1];
                System.arraycopy(args, 0, cmdArray, 0, sourceFileIndex);
                cmdArray[sourceFileIndex] = "@" + tmpFile;
            } else {
                cmdArray = new String[args.length];
                System.arraycopy(args, 0, cmdArray, 0, args.length);
            }

            if (System.getProperty("os.name").toLowerCase().indexOf("windows") > -1) {
                for (int i = 0; i < cmdArray.length; i++) {
                    if (cmdArray[i].indexOf("package-info") == -1) {
                        cmdArray[i] = cmdArray[i].replace('\\', '/');
                    }
                }
            }

            p = Runtime.getRuntime().exec(cmdArray);

            if (p.getErrorStream() != null) {
                StreamPrinter errorStreamPrinter = new StreamPrinter(p.getErrorStream(), "", System.out);
                errorStreamPrinter.start();
            }

            if (p.getInputStream() != null) {
                StreamPrinter infoStreamPrinter = new StreamPrinter(p.getInputStream(), "[INFO]", System.out);
                infoStreamPrinter.start();
            }

            if (p != null) {
                return p.waitFor() == 0 ? true : false;
            }
        } catch (SecurityException e) {
            System.err.println("[ERROR] SecurityException during exec() of compiler \"" + args[0] + "\".");
        } catch (InterruptedException e) {
            // ignore

        } catch (IOException e) {
            System.err.print("[ERROR] IOException during exec() of compiler \"" + args[0] + "\"");
            System.err.println(". Check your path environment variable.");
        } finally {
            if (tmpFile != null && tmpFile.exists()) {
                FileUtils.delete(tmpFile);
            }
        }

        return false;
    }

    private boolean isLongCommandLines(String args[]) {
        StringBuilder strBuffer = new StringBuilder();
        for (int i = 0; i < args.length; i++) {
            strBuffer.append(args[i]);
        }
        return strBuffer.toString().length() > 4096 ? true : false;
    }

    
}