java/src/main/com/google/appengine/tools/enhancer/Enhance.java

   1 // Copyright 2008 Google Inc.  All rights reserved.
   2
   3 package com.google.appengine.tools.enhancer;
   4
   5 import com.google.appengine.tools.info.SdkImplInfo;
   6 import com.google.appengine.tools.util.Logging;
   7
   8 import java.io.File;
   9 import java.io.FileWriter;
  10 import java.io.IOException;
  11 import java.io.PrintWriter;
  12 import java.net.URL;
  13 import java.net.URLClassLoader;
  14 import java.util.ArrayList;
  15 import java.util.Arrays;
  16 import java.util.HashSet;
  17 import java.util.List;
  18 import java.util.Set;
  19
  20 /**
  21  * The command-line interface for ORM enhancing. Usage:
  22  * <pre>
  23  * java -cp [classpath]
  24  *   com.google.appengine.tools.enhancer.Enhance [options] [jdo-files] [class-files]
  25  * where options can be
  26  *   -persistenceUnit [persistence-unit-name] : Name of a "persistence-unit" containing the classes
  27  *                                              to enhance
  28  *   -d [target-dir-name] : Write the enhanced classes to the specified directory
  29  *   -api [api-name] : Name of the API we are enhancing for (JDO, JPA). Default is JDO
  30  *   -enhancerName [name] : Name of the ClassEnhancer to use. Options ASM
  31  *   -checkonly : Just check the classes for enhancement status
  32  *   -v : verbose output
  33  *   -enhancerVersion [version] : The version of the DataNucleus enhancer to use, where version
  34  *                                corresponds to a directory under lib/opt/user/datanucleus in the
  35  *                                sdk.
  36  *
  37  * where classpath must contain the following
  38  *   - your classes
  39  *   - your meta-data files
  40  * <pre>
  41  *
  42  */
  43 public class Enhance {
  44
  45   static final String DATANUCLEUS_VERSION_ARG = "-enhancerVersion";
  46
  47   public static void main(String[] args) {
  48     Logging.initializeLogging();
  49     new Enhance(args);
  50   }
  51
  52   public Enhance(String[] args) {
  53     PrintWriter writer;
  54     File logFile;
  55
  56     try {
  57       logFile = File.createTempFile("enhance", ".log");
  58       writer = new PrintWriter(new FileWriter(logFile), true);
  59     } catch (IOException e) {
  60       throw new RuntimeException("Unable to enable logging.", e);
  61     }
  62
  63     try {
  64       Set<URL> targets = getEnhanceTargets();
  65       Enhancer enhancer = new Enhancer();
  66       enhancer.setTargets(targets);
  67       args = processArgs(enhancer, args);
  68       enhancer.setArgs(args);
  69       enhancer.execute();
  70     } catch (Exception e) {
  71       System.out.println("Encountered a problem: " + e.getMessage());
  72       System.out.println("Please see the logs [" + logFile.getAbsolutePath() +
  73           "] for further information.");
  74       e.printStackTrace(writer);
  75       System.exit(1);
  76     }
  77   }
  78
  79   /**
  80    * Some of the {@code args} are destined for us (App Engine) and some of the
  81    * args are destined for DataNucleus. This method processes the args that
  82    * are for us and returns a version of the provided array with the processed
  83    * args removed.
  84    */
  85   static String[] processArgs(Enhancer enhancer, String[] args) {
  86     List<String> processed = new ArrayList<String>();
  87     for (int i = 0; i < args.length; i++) {
  88       if (!args[i].startsWith("-") || !args[i].equals(DATANUCLEUS_VERSION_ARG)) {
  89         processed.add(args[i]);
  90         continue;
  91       }
  92       if (++i == args.length) {
  93         throw new IllegalArgumentException(
  94             String.format("Missing value for option %s", DATANUCLEUS_VERSION_ARG));
  95       }
  96       enhancer.setDatanucleusVersion(args[i]);
  97     }
  98     return processed.toArray(new String[processed.size()]);
  99   }
 100
 101   /**
 102    * We assume that every URL on our classpath is an enhancer target.
 103    * This is ugly, but it's how DataNucleus does it and is currently
 104    * the path of least resistance.
 105    */
 106   private Set<URL> getEnhanceTargets() {
 107     URLClassLoader myLoader = (URLClassLoader) getClass().getClassLoader();
 108     URL[] urls = myLoader.getURLs();
 109     Set<URL> enhanceTargets = new HashSet<URL>(Arrays.asList(urls));
 110     URL toolsJar = SdkImplInfo.getToolsApiJar();
 111     for (URL url : enhanceTargets) {
 112       if (url.sameFile(toolsJar)) {
 113         enhanceTargets.remove(toolsJar);
 114         break;
 115       }
 116     }
 117
 118     return enhanceTargets;
 119   }
 120 }