Merge pull request #6 from Toparvion/#5-composite-droplets

#5 Implemented support of composite droplets

Author: Toparvion

README.md

@@ -176,7 +176,7 @@ java -javaagent:$JMINT=$DROPLETS com.example.coolapp.Main
 Started with such arguments JVM will launch jMint and let it modify byte code of classes being loaded.  
 :warning: *Note that being unable to load an agent JVM will not start at all.*  
 :information_source: *`javaagent` is not singleton option for JVM. You may add as many agents as you want declaring them as separate  `javaagent` arguments on the JVM launch command.*  
-To ensure that your target methods have been modified correctly look for messages from class `tech.toparvion.jmint.TargetsTransformer` in the log (see _Logging_ section).
+To ensure that your target methods have been modified correctly look for messages from class `tech.toparvion.jmint.DropletsInjector` in the log (see _Logging_ section).
 
 # Limitations
 Unfortunately, source code of droplets' methods (the modifying code) can not be as rich and diverse as usual one.
@@ -206,9 +206,9 @@ Here's some sample messages emitted by jMint when `slf4j-simple` binding is pres
 ...
 [main] INFO tech.toparvion.jmint.JMintAgent - Droplets loading took: 1167 ms
 ... (later, at runtime) ...
-[main] INFO tech.toparvion.jmint.TargetsTransformer - Method 'sampleapp.standalone.painter.Painter.buildContent()' has been modified at AFTER cutpoint.
+[main] INFO tech.toparvion.jmint.DropletsInjector - Method 'sampleapp.standalone.painter.Painter.buildContent()' has been modified at AFTER.
 ...
-[main] INFO tech.toparvion.jmint.TargetsTransformer - Method 'sampleapp.standalone.painter.Painter#main' is skipped due to IGNORE cutpoint.
+[main] INFO tech.toparvion.jmint.DropletsInjector - Method 'sampleapp.standalone.painter.Painter#main' is skipped due to IGNORE.
 ```
 
 # Under the hood

build.gradle

@@ -1,5 +1,5 @@
 group 'toparvion'
-version '1.2'
+version '1.3'
 
 apply plugin: 'java'
 
@@ -21,7 +21,6 @@ dependencies {
     compile group: 'org.antlr', name: 'antlr4-runtime', version: '4.5.3'
     testCompile group: 'junit', name: 'junit', version: '4.11'
     testRuntime group: 'org.slf4j', name: 'slf4j-simple', version: '1.7.7'
-
 }
 
 jar {
@@ -40,14 +39,12 @@ jar {
 }
 
 task runPainterWithDebug(type: JavaExec, dependsOn: jar) {
-    classpath = sourceSets.test.runtimeClasspath /*+
-            project.files('src/test/java/sampleapp/standalone/painter/slf4j-simple-1.7.7.jar')*/
+    classpath = sourceSets.test.runtimeClasspath
+                /* + project.files('src/test/java/sampleapp/standalone/painter/slf4j-simple-1.7.7.jar')*/
     main 'sampleapp.standalone.painter.Painter'
     jvmArgs = ['-Dfile.encoding=UTF8',
                '-javaagent:build/libs/jmint-'+version+'.jar=' +
-                       'src/test/java/sampleapp/standalone/painter/DrawPaneDroplet.java;' +
-                       'src/test/java/sampleapp/standalone/painter/PainterDroplet.java;' +
-                       'src/test/resources/JFrameDroplet.java'
+                       'src/test/java/sampleapp/standalone/painter/composite-droplet.zip'
     ].toList()
     debug = true            // Gradle default debug port is 5005
 }

src/main/java/tech/toparvion/jmint/TargetsTransformer.java renamed to src/main/java/tech/toparvion/jmint/DropletsInjector.java

@@ -20,8 +20,8 @@
 /**
  * Created by Toparvion on 29.04.2016 12:50
  */
-class TargetsTransformer implements ClassFileTransformer {
-  private static final Logger log = LoggerFactory.getLogger(TargetsTransformer.class);
+class DropletsInjector implements ClassFileTransformer {
+  private static final Logger log = LoggerFactory.getLogger(DropletsInjector.class);
 
   /**
    * The package that is implicitly imported into every Javassist ClassPool instance and therefore should be considered
@@ -34,7 +34,7 @@ class TargetsTransformer implements ClassFileTransformer {
   private final Set<ClassLoader> knownLoaders = new HashSet<ClassLoader>();
   private final Set<String> knownPackages = new HashSet<String>();
 
-  TargetsTransformer(TargetsMap targetsMap) {
+  DropletsInjector(TargetsMap targetsMap) {
     this.targetsMap = targetsMap;
     this.pool = ClassPool.getDefault();
     // setup Javassist to dump all modified classes into directory specified via JVM option (if any)
@@ -106,7 +106,7 @@ public byte[] transform(ClassLoader loader,
           Cutpoint cutpoint = targetMethod.getCutpoint();
           MethodModifier modifier = cutpoint.getType().getModifier();
           modifier.apply(targetMethod.getText(), ctMethod, cutpoint.getAuxParams());
-          log.info("Method '{}' has been modified at {} cutpoint.", ctMethod.getLongName(), cutpoint);
+          log.info("Method '{}' has been modified at {}.", ctMethod.getLongName(), cutpoint);
 
         } catch (Exception e) {
           log.error(format("Failed to modify target method '%s#%s'. Skipped.",

src/main/java/tech/toparvion/jmint/JMintAgent.java

@@ -28,7 +28,7 @@ public static void premain(String agentArgs, Instrumentation inst) {
     if (targetsMap.isEmpty()) {
       log.warn("No droplets to apply left after arguments processing. No byte code will be modified.");
     } else {
-      inst.addTransformer(new TargetsTransformer(targetsMap));
+      inst.addTransformer(new DropletsInjector(targetsMap));
     }
   }
 

src/main/java/tech/toparvion/jmint/lang/DropletLoader.java

@@ -1,9 +1,6 @@
 package tech.toparvion.jmint.lang;
 
-import org.antlr.v4.runtime.ANTLRFileStream;
-import org.antlr.v4.runtime.BufferedTokenStream;
-import org.antlr.v4.runtime.CommonTokenStream;
-import org.antlr.v4.runtime.RecognitionException;
+import org.antlr.v4.runtime.*;
 import org.antlr.v4.runtime.tree.ParseTree;
 import org.antlr.v4.runtime.tree.ParseTreeWalker;
 import org.slf4j.Logger;
@@ -12,7 +9,9 @@
 import tech.toparvion.jmint.lang.gen.DroppingJavaParser;
 import tech.toparvion.jmint.model.TargetsMap;
 
-import java.io.IOException;
+import java.io.*;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipInputStream;
 
 /**
  * @author Toparvion
@@ -43,23 +42,61 @@ public static TargetsMap loadDroplets(String args) {
   }
 
   private static TargetsMap loadSingleDroplet(String dropletPath) throws IOException, RecognitionException {
-    DropletAssembler assembler = parseAndGetAssembler(dropletPath);
-    return assembler.getTargetsMap();
+    if (dropletPath.toLowerCase().endsWith(".jar") || dropletPath.toLowerCase().endsWith(".zip")) {
+      // the argument points to composite droplet so we should first extract its content from the archive
+      TargetsMap compositeTargetMap;
+      ZipInputStream zis = null;
+      try {
+        zis = new ZipInputStream(new FileInputStream(dropletPath));
+        compositeTargetMap = new TargetsMap();
+        ZipEntry nextEntry;
+        while ((nextEntry = zis.getNextEntry()) != null) {
+          if (!nextEntry.getName().toLowerCase().endsWith(".java")) continue;     // including directories
+          log.debug("Processing entry: {}", nextEntry.getName());
+          compositeTargetMap.putAll(parseDroplet(new NotClosingReader(zis)));
+          zis.closeEntry();
+        }
+      } finally {
+        if (zis != null) zis.close();
+      }
+      return compositeTargetMap;
+    }
+
+    // in case the argument is an ordinary file let's immediately pass it to ANTLR
+    return parseDroplet(new FileReader(dropletPath));
   }
 
-  private static DropletAssembler parseAndGetAssembler(String dropletPath) throws IOException {
-    ANTLRFileStream fileStream = new ANTLRFileStream(dropletPath);
-    DroppingJavaLexer lexer = new DroppingJavaLexer(fileStream);
-    BufferedTokenStream tokenStream = new CommonTokenStream(lexer);
-    DroppingJavaParser parser = new DroppingJavaParser(tokenStream);
+  private static TargetsMap parseDroplet(Reader dropletReader) throws IOException {
+    CharStream charStream                 = new ANTLRInputStream(dropletReader);
+    DroppingJavaLexer lexer               = new DroppingJavaLexer(charStream);
+    BufferedTokenStream tokenStream       = new CommonTokenStream(lexer);
+    DroppingJavaParser parser             = new DroppingJavaParser(tokenStream);
     parser.removeErrorListeners();
     parser.addErrorListener(new UnderlineErrorListener());
     ParseTree tree = parser.compilationUnit();
 
     DropletAssembler assembler = new DropletAssembler(tokenStream);
     ParseTreeWalker walker = new ParseTreeWalker();
     walker.walk(assembler, tree);
-    return assembler;
+    return assembler.getTargetsMap();
   }
 
+  /**
+   * A dummy implementation of {@link InputStreamReader} with stubbed {@link #close()} method. This is a way to prevent
+   * ANTLRInputStream from preliminary closing {@code ZipInputStream} during loading composite droplets.
+   */
+  private static class NotClosingReader extends InputStreamReader {
+
+    NotClosingReader(InputStream in) {
+      super(in);
+    }
+
+    @Override
+    public void close() throws IOException {
+      /* Here we're deliberately NOPing close operation as it must (and actually will) be done
+      on ZipEntry but not ZipInputStream. */
+    }
+  }
+
+
 }

src/test/java/sampleapp/standalone/painter/DrawPaneDroplet.java

@@ -357,7 +357,7 @@ public ActivateListener(JLabel pointCnt, JProgressBar prgs, String name, int poi
             this.points = points;
         }
         public void actionPerformed(ActionEvent event) {
-          //<editor-fold desc="This section was added just for testing of AFTER cutpoint">
+          //<editor-fold desc="This section was added just for testing AFTER cutpoint">
           if (tabbedPane.getTabCount() > 4) {
             throw new IllegalStateException("Too many tabs opened.");
           }