src/jdk.jlink/share/classes/jdk/tools/jlink/internal/plugins/VersionPropsPlugin.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.jlink/share/classes/jdk/tools/jlink/internal/plugins/VersionPropsPlugin.java Tue Oct 29 08:26:55 2019 -0700
@@ -0,0 +1,175 @@
+/*
+ * Copyright (c) 2019, 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. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.
+ */
+
+package jdk.tools.jlink.internal.plugins;
+
+import java.io.*;
+import java.nio.charset.*;
+import java.util.*;
+import java.util.function.*;
+import java.util.stream.*;
+import jdk.tools.jlink.plugin.*;
+import jdk.internal.org.objectweb.asm.*;
+
+import static java.lang.System.out;
+
+/**
+ * Base plugin to update a static field in java.lang.VersionProps
+ */
+abstract class VersionPropsPlugin implements Plugin {
+
+ private static final String VERSION_PROPS_CLASS
+ = "/java.base/java/lang/VersionProps.class";
+
+ private final String name;
+ private final String field;
+ private String value;
+
+ /**
+ * @param field The name of the java.lang.VersionProps field to be redefined
+ * @param option The option name
+ */
+ protected VersionPropsPlugin(String field, String option) {
+ this.field = field;
+ this.name = option;
+ }
+
+ /**
+ * Shorthand constructor for when the option name can be derived from the
+ * name of the field.
+ *
+ * @param field The name of the java.lang.VersionProps field to be redefined
+ */
+ protected VersionPropsPlugin(String field) {
+ this(field, field.toLowerCase().replace('_', '-'));
+ }
+
+ @Override
+ public String getName() {
+ return name;
+ }
+
+ @Override
+ public String getDescription() {
+ return PluginsResourceBundle.getDescription(name);
+ }
+
+ @Override
+ public Category getType() {
+ return Category.TRANSFORMER;
+ }
+
+ @Override
+ public boolean hasArguments() {
+ return true;
+ }
+
+ @Override
+ public boolean hasRawArgument() {
+ return true;
+ }
+
+ @Override
+ public String getArgumentsDescription() {
+ return PluginsResourceBundle.getArgument(name);
+ }
+
+ @Override
+ public void configure(Map<String, String> config) {
+ var v = config.get(name);
+ if (v == null)
+ throw new AssertionError();
+ value = v;
+ }
+
+ private boolean redefined = false;
+
+ private byte[] redefine(byte[] classFile) {
+
+ var cr = new ClassReader(classFile);
+ var cw = new ClassWriter(0);
+
+ cr.accept(new ClassVisitor(Opcodes.ASM7, cw) {
+
+ public MethodVisitor visitMethod(int access,
+ String name,
+ String desc,
+ String sig,
+ String[] xs)
+ {
+ if (name.equals("<clinit>"))
+ return new MethodVisitor(Opcodes.ASM7,
+ super.visitMethod(access,
+ name,
+ desc,
+ sig,
+ xs))
+ {
+
+ public void visitFieldInsn(int opcode,
+ String owner,
+ String name,
+ String desc)
+ {
+ if (opcode == Opcodes.PUTSTATIC
+ && name.equals(field))
+ {
+ // Discard the original value
+ super.visitInsn(Opcodes.POP);
+ // Load the value that we want
+ super.visitLdcInsn(value);
+ redefined = true;
+ }
+ super.visitFieldInsn(opcode, owner,
+ name, desc);
+ }
+
+ };
+ else
+ return super.visitMethod(access, name, desc, sig, xs);
+ }
+
+ }, 0);
+
+ return cw.toByteArray();
+
+ }
+
+ @Override
+ public ResourcePool transform(ResourcePool in, ResourcePoolBuilder out) {
+ in.transformAndCopy(res -> {
+ if (res.type().equals(ResourcePoolEntry.Type.CLASS_OR_RESOURCE)) {
+ if (res.path().equals(VERSION_PROPS_CLASS)) {
+ return res.copyWithContent(redefine(res.contentBytes()));
+ }
+ }
+ return res;
+ }, out);
+ if (!redefined)
+ throw new AssertionError(field);
+ return out.build();
+ }
+
+}