Java example source code file (InvokeDynamicPrintArgs.java)

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Java - Java tags/keywords

assertionerror, bsm, callsite, methodhandle, methodtype, mh_createtarget, mt_bsm, object, permissioncollection, printingcallsite, reflectiveoperationexception, security, string, testpolicy, throwable, util

The InvokeDynamicPrintArgs.java Java example source code

/*
 * Copyright (c) 2010, 2013, 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
 * @bug 7050328 8007035
 * @summary smoke test for invokedynamic instructions
 * @build indify.Indify
 * @compile InvokeDynamicPrintArgs.java
 * @run main/othervm
 *      indify.Indify
 *      --verify-specifier-count=3
 *      --expand-properties --classpath ${test.classes}
 *      --java test.java.lang.invoke.InvokeDynamicPrintArgs --check-output
 * @run main/othervm
 *      indify.Indify
 *      --expand-properties --classpath ${test.classes}
 *      --java test.java.lang.invoke.InvokeDynamicPrintArgs --security-manager
 */

package test.java.lang.invoke;

import java.util.*;
import java.io.*;

import java.lang.invoke.*;
import java.security.*;
import static java.lang.invoke.MethodHandles.*;
import static java.lang.invoke.MethodType.*;

public class InvokeDynamicPrintArgs {
    public static void main(String... av) throws Throwable {
        if (av.length > 0 && av[0].equals("--check-output"))  openBuf();
        if (av.length > 0 && av[0].equals("--security-manager"))  setSM();
        System.out.println("Printing some argument lists, starting with a empty one:");
        INDY_nothing().invokeExact();                 // BSM specifier #0 = {bsm}
        INDY_bar().invokeExact("bar arg", 1);         // BSM specifier #1 = {bsm2, Void.class, "void type"}
        INDY_bar2().invokeExact("bar2 arg", 222);     // BSM specifier #1 = (same)
        INDY_baz().invokeExact("baz arg", 2, 3.14);   // BSM specifier #2 = {bsm2, 1234.5}
        INDY_foo().invokeExact("foo arg");            // BSM specifier #0 = (same)
        // Hence, BSM specifier count should be 3.  See "--verify-specifier-count=3" above.
        System.out.println("Done printing argument lists.");
        closeBuf();
        checkConstantRefs();
    }

    private static void checkConstantRefs() throws Throwable {
        // check some constant references to its self class
        assertEquals(MT_bsm(), MH_bsm().type());
        assertEquals(MT_bsm2(), MH_bsm2().type());
        assertEquals(MT_bsm(), non_MH_bsm().type());
    }
    private static void assertEquals(Object exp, Object act) {
        if (exp == act || (exp != null && exp.equals(act)))  return;
        throw new AssertionError("not equal: "+exp+", "+act);
    }

    private static void setSM() {
        Policy.setPolicy(new TestPolicy());
        System.setSecurityManager(new SecurityManager());
    }

    private static PrintStream oldOut;
    private static ByteArrayOutputStream buf;
    private static void openBuf() {
        oldOut = System.out;
        buf = new ByteArrayOutputStream();
        System.setOut(new PrintStream(buf));
    }
    private static void closeBuf() {
        if (buf == null)  return;
        System.out.flush();
        System.setOut(oldOut);
        String[] haveLines = new String(buf.toByteArray()).split("[\n\r]+");
        for (String line : haveLines)  System.out.println(line);
        Iterator<String> iter = Arrays.asList(haveLines).iterator();
        for (String want : EXPECT_OUTPUT) {
            String have = iter.hasNext() ? iter.next() : "[EOF]";
            if (want.equals(have))  continue;
            System.err.println("want line: "+want);
            System.err.println("have line: "+have);
            throw new AssertionError("unexpected output: "+have);
        }
        if (iter.hasNext())
            throw new AssertionError("unexpected output: "+iter.next());
    }
    private static final String[] EXPECT_OUTPUT = {
        "Printing some argument lists, starting with a empty one:",
        "[test.java.lang.invoke.InvokeDynamicPrintArgs, nothing, ()void][]",
        "[test.java.lang.invoke.InvokeDynamicPrintArgs, bar, (String,int)void, class java.lang.Void, void type!, 1, 234.5, 67.5, 89][bar arg, 1]",
        "[test.java.lang.invoke.InvokeDynamicPrintArgs, bar2, (String,int)void, class java.lang.Void, void type!, 1, 234.5, 67.5, 89][bar2 arg, 222]",
        "[test.java.lang.invoke.InvokeDynamicPrintArgs, baz, (String,int,double)void, 1234.5][baz arg, 2, 3.14]",
        "[test.java.lang.invoke.InvokeDynamicPrintArgs, foo, (String)void][foo arg]",
        "Done printing argument lists."
    };

    private static boolean doPrint = true;
    private static void printArgs(Object bsmInfo, Object... args) {
        String message = bsmInfo+Arrays.deepToString(args);
        if (doPrint)  System.out.println(message);
    }
    private static MethodHandle MH_printArgs() throws ReflectiveOperationException {
        shouldNotCallThis();
        return lookup().findStatic(lookup().lookupClass(),
                                   "printArgs", methodType(void.class, Object.class, Object[].class));
    }

    private static CallSite bsm(Lookup caller, String name, MethodType type) throws ReflectiveOperationException {
        // ignore caller and name, but match the type:
        Object bsmInfo = Arrays.asList(caller, name, type);
        return new ConstantCallSite(MH_printArgs().bindTo(bsmInfo).asCollector(Object[].class, type.parameterCount()).asType(type));
    }
    private static MethodType MT_bsm() {
        shouldNotCallThis();
        return methodType(CallSite.class, Lookup.class, String.class, MethodType.class);
    }
    private static MethodHandle MH_bsm() throws ReflectiveOperationException {
        shouldNotCallThis();
        return lookup().findStatic(lookup().lookupClass(), "bsm", MT_bsm());
    }
    private static MethodHandle non_MH_bsm() throws ReflectiveOperationException {
        return lookup().findStatic(lookup().lookupClass(), "bsm", MT_bsm());
    }

    /* Example of a constant call site with user-data.
     * In this case, the user data is exactly the BSM data.
     * Note that a CCS with user data must use the "hooked" constructor
     * to bind the CCS itself into the resulting target.
     * A normal constructor would not allow a circular relation
     * between the CCS and its target.
     */
    public static class PrintingCallSite extends ConstantCallSite {
        final Lookup caller;
        final String name;
        final Object[] staticArgs;

        PrintingCallSite(Lookup caller, String name, MethodType type, Object... staticArgs) throws Throwable {
            super(type, MH_createTarget());
            this.caller = caller;
            this.name = name;
            this.staticArgs = staticArgs;
        }

        public MethodHandle createTarget() {
            try {
                return lookup().bind(this, "runTarget", genericMethodType(0, true)).asType(type());
            } catch (ReflectiveOperationException ex) {
                throw new RuntimeException(ex);
            }
        }

        public Object runTarget(Object... dynamicArgs) {
            List<Object> bsmInfo = new ArrayList<>(Arrays.asList(caller, name, type()));
            bsmInfo.addAll(Arrays.asList(staticArgs));
            printArgs(bsmInfo, dynamicArgs);
            return null;
        }

        private static MethodHandle MH_createTarget() throws ReflectiveOperationException {
            shouldNotCallThis();
            return lookup().findVirtual(lookup().lookupClass(), "createTarget", methodType(MethodHandle.class));
        }
    }
    private static CallSite bsm2(Lookup caller, String name, MethodType type, Object... arg) throws Throwable {
        // ignore caller and name, but match the type:
        return new PrintingCallSite(caller, name, type, arg);
    }
    private static MethodType MT_bsm2() {
        shouldNotCallThis();
        return methodType(CallSite.class, Lookup.class, String.class, MethodType.class, Object[].class);
    }
    private static MethodHandle MH_bsm2() throws ReflectiveOperationException {
        shouldNotCallThis();
        return lookup().findStatic(lookup().lookupClass(), "bsm2", MT_bsm2());
    }

    private static MethodHandle INDY_nothing() throws Throwable {
        shouldNotCallThis();
        return ((CallSite) MH_bsm().invoke(lookup(),
                                                  "nothing", methodType(void.class)
                                                  )).dynamicInvoker();
    }
    private static MethodHandle INDY_foo() throws Throwable {
        shouldNotCallThis();
        return ((CallSite) MH_bsm().invoke(lookup(),
                                                  "foo", methodType(void.class, String.class)
                                                  )).dynamicInvoker();
    }
    private static MethodHandle INDY_bar() throws Throwable {
        shouldNotCallThis();
        return ((CallSite) MH_bsm2().invoke(lookup(),
                                                  "bar", methodType(void.class, String.class, int.class)
                                                  , Void.class, "void type!", 1, 234.5F, 67.5, (long)89
                                                  )).dynamicInvoker();
    }
    private static MethodHandle INDY_bar2() throws Throwable {
        shouldNotCallThis();
        return ((CallSite) MH_bsm2().invoke(lookup(),
                                                  "bar2", methodType(void.class, String.class, int.class)
                                                  , Void.class, "void type!", 1, 234.5F, 67.5, (long)89
                                                  )).dynamicInvoker();
    }
    private static MethodHandle INDY_baz() throws Throwable {
        shouldNotCallThis();
        return ((CallSite) MH_bsm2().invoke(lookup(),
                                                  "baz", methodType(void.class, String.class, int.class, double.class)
                                                  , 1234.5
                                                  )).dynamicInvoker();
    }

    private static void shouldNotCallThis() {
        // if this gets called, the transformation has not taken place
        if (System.getProperty("InvokeDynamicPrintArgs.allow-untransformed") != null)  return;
        throw new AssertionError("this code should be statically transformed away by Indify");
    }

    static class TestPolicy extends Policy {
        final PermissionCollection permissions = new Permissions();
        TestPolicy() {
            permissions.add(new java.io.FilePermission("<", "read"));
        }
        public PermissionCollection getPermissions(ProtectionDomain domain) {
            return permissions;
        }

        public PermissionCollection getPermissions(CodeSource codesource) {
            return permissions;
        }

        public boolean implies(ProtectionDomain domain, Permission perm) {
            return permissions.implies(perm);
        }
    }
}