revamp JavaLauncher sequence to avoid problems with spaces on MacOS

com.ibm.wala.util/src/com/ibm/wala/util/processes/JavaLauncher.java

@@ -25,21 +25,31 @@ import com.ibm.wala.util.PlatformUtil;
 public class JavaLauncher extends Launcher {
 
   /**
-   * @param programArgs arguments to be passed to the Java program
-   * @param mainClass Declaring class of the main() method to run.
-   * @param classpathEntries Paths that will be added to the default classpath
+   * @param programArgs
+   *          arguments to be passed to the Java program
+   * @param mainClass
+   *          Declaring class of the main() method to run.
+   * @param classpathEntries
+   *          Paths that will be added to the default classpath
    */
   public static JavaLauncher make(String programArgs, String mainClass, List<String> classpathEntries, Logger logger) {
     return new JavaLauncher(programArgs, mainClass, true, classpathEntries, false, false, logger);
   }
 
   /**
-   * @param programArgs arguments to be passed to the Java program
-   * @param mainClass Declaring class of the main() method to run.
-   * @param inheritClasspath Should the spawned process inherit all classpath entries of the currently running process?
-   * @param classpathEntries Paths that will be added to the default classpath
-   * @param captureOutput should the launcher capture the stdout from the subprocess?
-   * @param captureErr should the launcher capture the stderr from the subprocess?
+   * @param programArgs
+   *          arguments to be passed to the Java program
+   * @param mainClass
+   *          Declaring class of the main() method to run.
+   * @param inheritClasspath
+   *          Should the spawned process inherit all classpath entries of the
+   *          currently running process?
+   * @param classpathEntries
+   *          Paths that will be added to the default classpath
+   * @param captureOutput
+   *          should the launcher capture the stdout from the subprocess?
+   * @param captureErr
+   *          should the launcher capture the stderr from the subprocess?
    */
   public static JavaLauncher make(String programArgs, String mainClass, boolean inheritClasspath, List<String> classpathEntries,
       boolean captureOutput, boolean captureErr, Logger logger) {
@@ -60,7 +70,8 @@ public class JavaLauncher extends Launcher {
   private final String mainClass;
 
   /**
-   * Should the spawned process inherit all classpath entries of the currently running process?
+   * Should the spawned process inherit all classpath entries of the currently
+   * running process?
    */
   private final boolean inheritClasspath;
 
@@ -83,17 +94,17 @@ public class JavaLauncher extends Launcher {
    * A {@link Thread} which spins and drains stderr of the running process.
    */
   private Thread stdErrDrain;
-  
+
   /**
    * Absolute path of the 'java' executable to use.
    */
   private String javaExe;
-  
+
   /**
    * Extra args to pass to the JVM
    */
   private String vmArgs;
-  
+
   /**
    * The last process returned by a call to start() on this object.
    */
@@ -110,7 +121,7 @@ public class JavaLauncher extends Launcher {
     }
     this.javaExe = defaultJavaExe();
   }
-  
+
   public String getJavaExe() {
     return javaExe;
   }
@@ -162,24 +173,54 @@ public class JavaLauncher extends Launcher {
   public Process start() throws IllegalArgumentException, IOException {
     String cp = makeClasspath();
 
-    String heap = " -Xmx800M ";
+    String heap = "-Xmx800M";
 
     // on Mac, need to pass an extra parameter so we can cleanly kill child
     // Java process
-    String signalParam = PlatformUtil.onMacOSX() ? " -Xrs " : "";
+    String signalParam = PlatformUtil.onMacOSX() ? "-Xrs" : null;
 
-    String ea = enableAssertions ? " -ea " : "";
-    String vmArgs = getVmArgs() == null ? "" : getVmArgs();
+    List<String> cmd = new ArrayList<String>();
 
-    String cmd = javaExe + heap + signalParam + cp + " " + makeLibPath() + " " + ea + " " + vmArgs + " " + getMainClass() + " " + getProgramArgs();
+    cmd.add(javaExe);
+    cmd.add(heap);
+    if (signalParam != null) {
+      cmd.add(signalParam);
+    }
+    cmd.add("-classpath");
+    cmd.add(cp);
+    String libPath = makeLibPath();
+    if (libPath != null) {
+      cmd.add(libPath);
+    }
+    if (enableAssertions) {
+      cmd.add("-ea");
+    }
+    if (vmArgs != null) {
+      String[] vmArgs = getVmArgs().split(" +");
+      for (String s : vmArgs) {
+        if (s.length() > 0) {
+          cmd.add(s);
+        }
+      }
+    }
+    cmd.add(getMainClass());
+    if (getProgramArgs() != null) {
+      String[] pa = getProgramArgs().split(" ");
+      for (String s : pa) {
+        cmd.add(s);
+      }
+    }
 
-    Process p = spawnProcess(cmd);
+    String[] cmds = new String[cmd.size()];
+    cmd.toArray(cmds);
+
+    Process p = spawnProcess(cmds);
     stdErrDrain = isCaptureErr() ? captureStdErr(p) : drainStdErr(p);
     stdOutDrain = isCaptureOutput() ? captureStdOut(p) : drainStdOut(p);
     lastProcess = p;
     return p;
   }
-  
+
   public Process getLastProcess() {
     return lastProcess;
   }
@@ -187,7 +228,7 @@ public class JavaLauncher extends Launcher {
   private String makeLibPath() {
     String libPath = System.getProperty("java.library.path");
     if (libPath == null) {
-      return "";
+      return null;
     } else {
       return "-Djava.library.path=" + quoteStringIfNeeded(libPath);
     }
@@ -195,7 +236,9 @@ public class JavaLauncher extends Launcher {
 
   /**
    * Wait for the spawned process to terminate.
-   * @throws IllegalStateException if the process has not been started
+   * 
+   * @throws IllegalStateException
+   *           if the process has not been started
    */
   public void join() {
     if (stdOutDrain == null || stdErrDrain == null) {
@@ -224,20 +267,21 @@ public class JavaLauncher extends Launcher {
   private String makeClasspath() {
     String cp = inheritClasspath ? System.getProperty("java.class.path") : "";
     if (getXtraClassPath() == null || getXtraClassPath().isEmpty()) {
-      return " -classpath " + quoteStringIfNeeded(cp);
+      return quoteStringIfNeeded(cp);
     } else {
       for (Iterator<String> it = getXtraClassPath().iterator(); it.hasNext();) {
         cp += File.pathSeparatorChar;
         cp += (String) it.next();
       }
-      return " -classpath " + quoteStringIfNeeded(cp);
+      return quoteStringIfNeeded(cp);
     }
   }
 
   /**
-   * If the input string contains a space, quote it (for use as a classpath). TODO: Figure out how to make a Mac happy with quotes.
-   * Trailing separators are unsafe, so we have to escape the last backslash (if present and unescaped), so it doesn't escape the
-   * closing quote.
+   * If the input string contains a space, quote it (for use as a classpath).
+   * TODO: Figure out how to make a Mac happy with quotes. Trailing separators
+   * are unsafe, so we have to escape the last backslash (if present and
+   * unescaped), so it doesn't escape the closing quote.
    */
   public static String quoteStringIfNeeded(String s) {
     s = s.trim();