6715251: javap should be consistent with javac and return 2 if given no arguments

Reviewed-by: ksrini

src/share/classes/com/sun/tools/javap/JavapTask.java

@@ -306,14 +306,32 @@ public class JavapTask implements DisassemblerTool.DisassemblerTask {
         };
     }
 
+    /** Result codes.
+     */
+    static final int
+        EXIT_OK = 0,        // Compilation completed with no errors.
+        EXIT_ERROR = 1,     // Completed but reported errors.
+        EXIT_CMDERR = 2,    // Bad command-line arguments
+        EXIT_SYSERR = 3,    // System error or resource exhaustion.
+        EXIT_ABNORMAL = 4;  // Compiler terminated abnormally
+
     int run(String[] args) {
         try {
             handleOptions(args);
+
+            // the following gives consistent behavior with javac
+            if (classes == null || classes.size() == 0) {
+                if (options.help || options.version || options.fullVersion)
+                    return EXIT_OK;
+                else
+                    return EXIT_CMDERR;
+            }
+
             boolean ok = run();
-            return ok ? 0 : 1;
+            return ok ? EXIT_OK : EXIT_ERROR;
         } catch (BadArgs e) {
             diagnosticListener.report(createDiagnostic(e.key, e.args));
-            return 1;
+            return EXIT_CMDERR;
         } catch (InternalError e) {
             Object[] e_args;
             if (e.getCause() == null)
@@ -324,7 +342,7 @@ public class JavapTask implements DisassemblerTool.DisassemblerTask {
                 System.arraycopy(e.args, 0, e_args, 1, e.args.length);
             }
             diagnosticListener.report(createDiagnostic("err.internal.error", e_args));
-            return 1;
+            return EXIT_ABNORMAL;
         } finally {
             log.flush();
         }
@@ -349,8 +367,7 @@ public class JavapTask implements DisassemblerTool.DisassemblerTask {
             fileManager = getDefaultFileManager(diagnosticListener, log);
 
         Iterator<String> iter = args.iterator();
-        if (!iter.hasNext())
-            options.help = true;
+        boolean noArgs = !iter.hasNext();
 
         while (iter.hasNext()) {
             String arg = iter.next();
@@ -370,9 +387,15 @@ public class JavapTask implements DisassemblerTool.DisassemblerTask {
             ((JavapFileManager) fileManager).setIgnoreSymbolFile(true);
 
         if ((classes == null || classes.size() == 0) &&
-                !(options.help || options.version || options.fullVersion)) {
+                !(noArgs || options.help || options.version || options.fullVersion)) {
             throw new BadArgs("err.no.classes.specified");
         }
+
+        if (noArgs || options.help)
+            showHelp();
+
+        if (options.version || options.fullVersion)
+            showVersion(options.fullVersion);
     }
 
     private void handleOption(String name, Iterator<String> rest) throws BadArgs {
@@ -405,14 +428,8 @@ public class JavapTask implements DisassemblerTool.DisassemblerTask {
     }
 
     public boolean run() {
-        if (options.help)
-            showHelp();
-
-        if (options.version || options.fullVersion)
-            showVersion(options.fullVersion);
-
         if (classes == null || classes.size() == 0)
-            return true;
+            return false;
 
         context.put(PrintWriter.class, log);
         ClassWriter classWriter = ClassWriter.instance(context);

test/tools/javap/T4876942.java

@@ -23,7 +23,7 @@
 
 /*
  * @test
- * @bug 4876942
+ * @bug 4876942 6715251
  * @summary javap invoked without args does not print help screen
  */
 
@@ -48,7 +48,7 @@ public class T4876942 {
         PrintWriter out = new PrintWriter(sw);
         //sun.tools.javap.Main.entry(args);
         int rc = com.sun.tools.javap.Main.run(args, out);
-        if (rc != 0)
+        if (rc != (args.length == 0 ? 2 : 0))
             throw new Error("javap failed. rc=" + rc);
         out.close();
         return sw.toString();

test/tools/javap/T6715251.java

+/*
+ * Copyright 2008 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+import java.io.*;
+import java.util.*;
+
+/*
+ * @test
+ * @bug 6715251
+ * @summary javap should be consistent with javac and return 2 if given no arguments
+ */
+
+public class T6715251 {
+    public static void main(String... args) throws Exception {
+        new T6715251().run();
+    }
+
+    void run() throws Exception {
+        String testClasses = System.getProperty("test.classes", ".");
+
+        test(2);
+        test(0, "-help");
+        test(0, "-version");
+        test(0, "-fullversion");
+        test(0, "-classpath", testClasses, "T6715251");
+
+        if (errors > 0)
+            throw new Exception(errors + " errors received");
+    }
+
+    void test(int expect, String ... args) {
+        int rc = javap(args);
+        if (rc != expect)
+            error("bad result: expected: " + expect + ", found " + rc + "\n"
+                  + log);
+
+    }
+
+    int javap(String... args) {
+        StringWriter sw = new StringWriter();
+        PrintWriter pw = new PrintWriter(sw);
+        int rc = com.sun.tools.javap.Main.run(args, pw);
+        log = sw.toString();
+        return rc;
+    }
+
+    void error(String msg) {
+        System.err.println(msg);
+        errors++;
+    }
+
+    String log;
+    int errors;
+}
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