langtools/test/tools/javac/MethodParameters.java
changeset 15031 c4fad55a5681
child 15036 b60e18ab9dd7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/langtools/test/tools/javac/MethodParameters.java	Sat Dec 29 17:33:17 2012 -0800
@@ -0,0 +1,343 @@
+/*
+ * Copyright (c) 2012, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @summary javac should generate method parameters correctly.
+ */
+// key: opt.arg.parameters
+import com.sun.tools.classfile.*;
+import com.sun.tools.javac.file.JavacFileManager;
+import com.sun.tools.javac.main.Main;
+import com.sun.tools.javac.util.Context;
+import com.sun.tools.javac.util.Name;
+import com.sun.tools.javac.util.Names;
+import java.io.*;
+import javax.lang.model.element.*;
+import java.util.*;
+
+public class MethodParameters {
+
+    static final String Foo_name = "Foo";
+    static final String Foo_contents =
+        "public class Foo {\n" +
+        "  Foo() {}\n" +
+        "  void foo0() {}\n" +
+        "  void foo2(int j, int k) {}\n" +
+        "}";
+    static final String Bar_name = "Bar";
+    static final String Bar_contents =
+        "public class Bar {\n" +
+        "  Bar(int i) {}" +
+        "  Foo foo() { return new Foo(); }\n" +
+        "}";
+    static final String Baz_name = "Baz";
+    static final String Baz_contents =
+        "public class Baz {\n" +
+        "  int baz;" +
+        "  Baz(int i) {}" +
+        "}";
+    static final String Qux_name = "Qux";
+    static final String Qux_contents =
+        "public class Qux extends Baz {\n" +
+        "  Qux(int i) { super(i); }" +
+        "}";
+    static final File classesdir = new File("methodparameters");
+
+    public static void main(String... args) throws Exception {
+        new MethodParameters().run();
+    }
+
+    void run() throws Exception {
+        classesdir.mkdir();
+        final File Foo_java =
+            writeFile(classesdir, Foo_name + ".java", Foo_contents);
+        final File Bar_java =
+            writeFile(classesdir, Bar_name + ".java", Bar_contents);
+        final File Baz_java =
+            writeFile(classesdir, Baz_name + ".java", Baz_contents);
+        System.err.println("Test compile with -parameter");
+        compile("-parameters", "-d", classesdir.getPath(), Foo_java.getPath());
+        // First test: make sure javac doesn't choke to death on
+        // MethodParameter attributes
+        System.err.println("Test compile with classfile containing MethodParameter attributes");
+        compile("-parameters", "-d", classesdir.getPath(),
+                "-cp", classesdir.getPath(), Bar_java.getPath());
+        System.err.println("Examine class foo");
+        checkFoo();
+        checkBar();
+        System.err.println("Test debug information conflict");
+        compile("-g", "-parameters", "-d", classesdir.getPath(),
+                "-cp", classesdir.getPath(), Baz_java.getPath());
+        System.err.println("Introducing debug information conflict");
+        Baz_java.delete();
+        modifyBaz(false);
+        System.err.println("Checking language model");
+        inspectBaz();
+        System.err.println("Permuting attributes");
+        modifyBaz(true);
+        System.err.println("Checking language model");
+        inspectBaz();
+
+        if(0 != errors)
+            throw new Exception("MethodParameters test failed with " +
+                                errors + " errors");
+    }
+
+    void inspectBaz() throws Exception {
+        final File Qux_java =
+            writeFile(classesdir, Qux_name + ".java", Qux_contents);
+        final String[] args = { "-XDsave-parameter-names", "-d",
+                                classesdir.getPath(),
+                                "-cp", classesdir.getPath(),
+                                Qux_java.getPath() };
+        final StringWriter sw = new StringWriter();
+        final PrintWriter pw = new PrintWriter(sw);
+
+        // We need to be able to crack open javac and look at its data
+        // structures.  We'll rig up a compiler instance, but keep its
+        // Context, thus allowing us to get at the ClassReader.
+        Context context = new Context();
+        Main comp =  new Main("javac", pw);
+        JavacFileManager.preRegister(context);
+
+        // Compile Qux, which uses Baz.
+        comp.compile(args, context);
+        pw.close();
+        final String out = sw.toString();
+        if (out.length() > 0)
+            System.err.println(out);
+
+        // Now get the class reader, construct a name for Baz, and load it.
+        com.sun.tools.javac.jvm.ClassReader cr =
+            com.sun.tools.javac.jvm.ClassReader.instance(context);
+        Name name = Names.instance(context).fromString(Baz_name);
+
+        // Now walk down the language model and check the name of the
+        // parameter.
+        final Element baz = cr.loadClass(name);
+        for (Element e : baz.getEnclosedElements()) {
+            if (e instanceof ExecutableElement) {
+                final ExecutableElement ee = (ExecutableElement) e;
+                final List<? extends VariableElement> params =
+                    ee.getParameters();
+                if (1 != params.size())
+                    throw new Exception("Classfile Baz badly formed: wrong number of methods");
+                final VariableElement param = params.get(0);
+                if (!param.getSimpleName().contentEquals("baz")) {
+                    errors++;
+                    System.err.println("javac did not correctly resolve the metadata conflict, parameter's name reads as " + param.getSimpleName());
+                } else
+                    System.err.println("javac did correctly resolve the metadata conflict");
+            }
+        }
+    }
+
+    void modifyBaz(boolean flip) throws Exception {
+        final File Baz_class = new File(classesdir, Baz_name + ".class");
+        final ClassFile baz = ClassFile.read(Baz_class);
+        final int ind = baz.constant_pool.getUTF8Index("baz");
+        MethodParameters_attribute mpattr = null;
+        int mpind = 0;
+        Code_attribute cattr = null;
+        int cind = 0;
+
+        // Find the indexes of the MethodParameters and the Code attributes
+        if (baz.methods.length != 1)
+            throw new Exception("Classfile Baz badly formed: wrong number of methods");
+        if (!baz.methods[0].getName(baz.constant_pool).equals("<init>"))
+            throw new Exception("Classfile Baz badly formed: method has name " +
+                                baz.methods[0].getName(baz.constant_pool));
+        for (int i = 0; i < baz.methods[0].attributes.attrs.length; i++) {
+            if (baz.methods[0].attributes.attrs[i] instanceof
+                MethodParameters_attribute) {
+                mpattr = (MethodParameters_attribute)
+                    baz.methods[0].attributes.attrs[i];
+                mpind = i;
+            } else if (baz.methods[0].attributes.attrs[i] instanceof
+                       Code_attribute) {
+                cattr = (Code_attribute) baz.methods[0].attributes.attrs[i];
+                cind = i;
+            }
+        }
+        if (null == mpattr)
+            throw new Exception("Classfile Baz badly formed: no method parameters info");
+        if (null == cattr)
+            throw new Exception("Classfile Baz badly formed: no local variable table");
+
+        int flags = mpattr.method_parameter_table[0].flags;
+
+        // Alter the MethodParameters attribute, changing the name of
+        // the parameter from i to baz.  This requires Black Magic...
+        //
+        // The (well-designed) classfile library (correctly) does not
+        // allow us to mess around with the attribute data structures,
+        // or arbitrarily generate new ones.
+        //
+        // Instead, we install a new subclass of Attribute that
+        // hijacks the Visitor pattern and outputs the sequence of
+        // bytes that we want.  This only works in this particular
+        // instance, because we know we'll only every see one kind of
+        // visitor.
+        //
+        // If anyone ever changes the makeup of the Baz class, or
+        // tries to install some kind of visitor that gets run prior
+        // to serialization, this will break.
+        baz.methods[0].attributes.attrs[mpind] =
+            new Attribute(mpattr.attribute_name_index,
+                          mpattr.attribute_length) {
+                public <R, D> R accept(Visitor<R, D> visitor, D data) {
+                    if (data instanceof ByteArrayOutputStream) {
+                        ByteArrayOutputStream out =
+                            (ByteArrayOutputStream) data;
+                        out.write(1);
+                        out.write((ind >> 8) & 0xff);
+                        out.write(ind & 0xff);
+                        out.write((flags >> 24) & 0xff);
+                        out.write((flags >> 16) & 0xff);
+                        out.write((flags >> 8) & 0xff);
+                        out.write(flags & 0xff);
+                    } else
+                        throw new RuntimeException("Output stream is of type " + data.getClass() + ", which is not handled by this test.  Update the test and it should work.");
+                    return null;
+                }
+            };
+
+        // Flip the code and method attributes.  This is for checking
+        // that order doesn't matter.
+        if (flip) {
+            baz.methods[0].attributes.attrs[mpind] = cattr;
+            baz.methods[0].attributes.attrs[cind] = mpattr;
+        }
+
+        new ClassWriter().write(baz, Baz_class);
+    }
+
+    // Run a bunch of structural tests on foo to make sure it looks right.
+    void checkFoo() throws Exception {
+        final File Foo_class = new File(classesdir, Foo_name + ".class");
+        final ClassFile foo = ClassFile.read(Foo_class);
+        for (int i = 0; i < foo.methods.length; i++) {
+            System.err.println("Examine method Foo." + foo.methods[i].getName(foo.constant_pool));
+            if (foo.methods[i].getName(foo.constant_pool).equals("foo2")) {
+                for (int j = 0; j < foo.methods[i].attributes.attrs.length; j++)
+                    if (foo.methods[i].attributes.attrs[j] instanceof
+                        MethodParameters_attribute) {
+                        MethodParameters_attribute mp =
+                            (MethodParameters_attribute)
+                            foo.methods[i].attributes.attrs[j];
+                        System.err.println("Foo.foo2 should have 2 parameters: j and k");
+                        if (2 != mp.method_parameter_table_length)
+                            error("expected 2 method parameter entries in foo2, got " +
+                                  mp.method_parameter_table_length);
+                        else if (!foo.constant_pool.getUTF8Value(mp.method_parameter_table[0].name_index).equals("j"))
+                            error("expected first parameter to foo2 to be \"j\", got \"" +
+                                  foo.constant_pool.getUTF8Value(mp.method_parameter_table[0].name_index) +
+                                  "\" instead");
+                        else if  (!foo.constant_pool.getUTF8Value(mp.method_parameter_table[1].name_index).equals("k"))
+                            error("expected first parameter to foo2 to be \"k\", got \"" +
+                                  foo.constant_pool.getUTF8Value(mp.method_parameter_table[1].name_index) +
+                                  "\" instead");
+                    }
+            }
+            else if (foo.methods[i].getName(foo.constant_pool).equals("<init>")) {
+                for (int j = 0; j < foo.methods[i].attributes.attrs.length; j++) {
+                    if (foo.methods[i].attributes.attrs[j] instanceof
+                        MethodParameters_attribute)
+                        error("Zero-argument constructor shouldn't have MethodParameters");
+                }
+            }
+            else if (foo.methods[i].getName(foo.constant_pool).equals("foo0")) {
+                for (int j = 0; j < foo.methods[i].attributes.attrs.length; j++)
+                    if (foo.methods[i].attributes.attrs[j] instanceof
+                        MethodParameters_attribute)
+                        error("Zero-argument method shouldn't have MethodParameters");
+            }
+            else
+                error("Unknown method " + foo.methods[i].getName(foo.constant_pool) + " showed up in class Foo");
+        }
+    }
+
+    // Run a bunch of structural tests on Bar to make sure it looks right.
+    void checkBar() throws Exception {
+        final File Bar_class = new File(classesdir, Bar_name + ".class");
+        final ClassFile bar = ClassFile.read(Bar_class);
+        for (int i = 0; i < bar.methods.length; i++) {
+            System.err.println("Examine method Bar." + bar.methods[i].getName(bar.constant_pool));
+            if (bar.methods[i].getName(bar.constant_pool).equals("<init>")) {
+                for (int j = 0; j < bar.methods[i].attributes.attrs.length; j++)
+                    if (bar.methods[i].attributes.attrs[j] instanceof
+                        MethodParameters_attribute) {
+                        MethodParameters_attribute mp =
+                            (MethodParameters_attribute)
+                            bar.methods[i].attributes.attrs[j];
+                        System.err.println("Bar constructor should have 1 parameter: i");
+                        if (1 != mp.method_parameter_table_length)
+                            error("expected 1 method parameter entries in constructor, got " +
+                                  mp.method_parameter_table_length);
+                        else if (!bar.constant_pool.getUTF8Value(mp.method_parameter_table[0].name_index).equals("i"))
+                            error("expected first parameter to foo2 to be \"i\", got \"" +
+                                  bar.constant_pool.getUTF8Value(mp.method_parameter_table[0].name_index) +
+                                  "\" instead");
+                    }
+            }
+            else if (bar.methods[i].getName(bar.constant_pool).equals("foo")) {
+                for (int j = 0; j < bar.methods[i].attributes.attrs.length; j++) {
+                    if (bar.methods[i].attributes.attrs[j] instanceof
+                        MethodParameters_attribute)
+                        error("Zero-argument constructor shouldn't have MethodParameters");
+                }
+            }
+        }
+    }
+
+    String compile(String... args) throws Exception {
+        System.err.println("compile: " + Arrays.asList(args));
+        StringWriter sw = new StringWriter();
+        PrintWriter pw = new PrintWriter(sw);
+        int rc = com.sun.tools.javac.Main.compile(args, pw);
+        pw.close();
+        String out = sw.toString();
+        if (out.length() > 0)
+            System.err.println(out);
+        if (rc != 0)
+            error("compilation failed, rc=" + rc);
+        return out;
+    }
+
+    File writeFile(File dir, String path, String body) throws IOException {
+        File f = new File(dir, path);
+        f.getParentFile().mkdirs();
+        FileWriter out = new FileWriter(f);
+        out.write(body);
+        out.close();
+        return f;
+    }
+
+    void error(String msg) {
+        System.err.println("Error: " + msg);
+        errors++;
+    }
+
+    int errors;
+}