Adding a prototype of CodeBuilder to build a sequence of TreeBuilder calls to construct a given AST.
/*
* 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.
*
* 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 9999999
* @summary XXX
* @library /tools/lib
* @modules
* jdk.compiler/com.sun.tools.javac.api
* jdk.compiler/com.sun.tools.javac.main
* @build toolbox.ToolBox CodeBuilder
* @run main ASTBuilder
*/
import java.net.URI;
import java.util.Arrays;
import java.util.function.Consumer;
import javax.tools.JavaCompiler;
import javax.tools.JavaFileObject;
import javax.tools.SimpleJavaFileObject;
import javax.tools.ToolProvider;
import com.sun.source.tree.CompilationUnitTree;
import com.sun.source.tree.Tree;
import com.sun.source.util.JavacTask;
import com.sun.source.util.TreeBuilder;
import com.sun.source.util.TreeBuilder.*;
import com.sun.source.util.Trees;
import com.sun.source.util.TreeScanner;
import javax.tools.StandardLocation;
import com.sun.source.tree.ClassTree;
import com.sun.source.tree.IdentifierTree;
import com.sun.source.tree.MemberReferenceTree;
import com.sun.source.tree.MemberSelectTree;
import com.sun.source.tree.MethodTree;
import com.sun.source.tree.VariableTree;
import toolbox.ToolBox.MemoryFileManager;
public class ASTBuilder {
public static void main(String[] args) throws Exception {
runTest("class Test {" +
" int x;" +
"}",
U -> U._class("Test", C -> C.field("x", Type::_int)));
runTest("class Test {" +
" int x1 = 2;" +
" int x2 = 2 + x1;" +
"}");
}
private static void runTest(String expectedCode, Consumer<CompilationUnit> actualBuilder) throws Exception {
final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();
assert tool != null;
JavacTask expectedTask = (JavacTask) tool.getTask(null, null, null,
null, null, Arrays.asList(new MyFileObject(expectedCode)));
String expectedDump = dumpTree(expectedTask.parse().iterator().next());
JavacTask ct = (JavacTask) tool.getTask(null, null, null,
null, null, Arrays.asList(new MyFileObject("")));
ct.parse(); //init javac
Trees t = Trees.instance(ct);
TreeBuilder builder = t.getTreeBuilder();
CompilationUnitTree cut = builder.createCompilationUnitTree(actualBuilder);
String actualDump = dumpTree(cut);
if (!actualDump.equals(expectedDump)) {
throw new AssertionError("Expected and actual dump differ. Expected: " + expectedDump + "; actual: " + actualDump);
}
}
private static void runTest(String expectedCode) throws Exception {
final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();
assert tool != null;
JavacTask expectedTask = (JavacTask) tool.getTask(null, null, null,
null, null, Arrays.asList(new MyFileObject(expectedCode)));
CompilationUnitTree expectedCUT = expectedTask.parse().iterator().next();
String builderCode = CodeBuilder.buildCodeToGenerate(expectedCUT, "builder");
System.err.println("builderCode:");
System.err.println(builderCode);
String expectedCodeGen = "import com.sun.source.tree.*; import com.sun.source.util.*; public class CodeGen { public static CompilationUnitTree build(TreeBuilder builder) { return " + builderCode + "; } }";
String expectedDump = dumpTree(expectedCUT);
try (MemoryFileManager mfm = new MemoryFileManager(tool.getStandardFileManager(null, null, null))) {
Boolean res = tool.getTask(null, mfm, null,
null, null, Arrays.asList(new MyFileObject(expectedCodeGen)))
.call();
if (!res) {
throw new IllegalStateException("Could not compile the generated code!");
}
ClassLoader codeCL = new ClassLoader(ASTBuilder.class.getClassLoader()) {
@Override
protected java.lang.Class<?> findClass(String name) throws ClassNotFoundException {
byte[] bytecode = mfm.getFileBytes(StandardLocation.CLASS_OUTPUT, name);
if (bytecode != null) {
return defineClass(name, bytecode, 0, bytecode.length);
}
return super.findClass(name);
}
};
JavacTask ct = (JavacTask) tool.getTask(null, null, null,
null, null, Arrays.asList(new MyFileObject("")));
ct.parse(); //init javac
Trees t = Trees.instance(ct);
TreeBuilder builder = t.getTreeBuilder();
java.lang.Class<?> codeGen = codeCL.loadClass("CodeGen");
CompilationUnitTree cut = (CompilationUnitTree) codeGen.getDeclaredMethod("build", TreeBuilder.class).invoke(null, builder);
String actualDump = dumpTree(cut);
if (!actualDump.equals(expectedDump)) {
throw new AssertionError("Expected and actual dump differ. Expected: " + expectedDump + "; actual: " + actualDump);
}
}
}
static String dumpTree(Tree t) {
StringBuilder result = new StringBuilder();
new TreeScanner<Void, Void>() {
String sep = "";
@Override
public Void scan(Tree tree, Void p) {
result.append(sep);
sep = " ";
if (tree == null) {
result.append("null");
return null;
}
result.append("(");
result.append(tree.getKind().name());
super.scan(tree, p);
result.append(")");
return null;
}
@Override
public Void scan(Iterable<? extends Tree> nodes, Void p) {
result.append(sep);
sep = " ";
if (nodes == null) {
result.append("null");
return null;
}
result.append("(");
super.scan(nodes, p);
result.append(")");
return null;
}
@Override
public Void visitIdentifier(IdentifierTree node, Void p) {
result.append(node.getName());
return super.visitIdentifier(node, p);
}
@Override
public Void visitMemberSelect(MemberSelectTree node, Void p) {
result.append(node.getIdentifier());
return super.visitMemberSelect(node, p);
}
@Override
public Void visitMemberReference(MemberReferenceTree node, Void p) {
result.append(node.getName());
return super.visitMemberReference(node, p);
}
@Override
public Void visitClass(ClassTree node, Void p) {
result.append(node.getSimpleName());
return super.visitClass(node, p);
}
@Override
public Void visitMethod(MethodTree node, Void p) {
result.append(node.getName());
return super.visitMethod(node, p);
}
@Override
public Void visitVariable(VariableTree node, Void p) {
result.append(node.getName());
return super.visitVariable(node, p);
}
}.scan(t, null);
return result.toString();
}
static class MyFileObject extends SimpleJavaFileObject {
private String text;
public MyFileObject(String text) {
super(URI.create("myfo:/Test.java"), JavaFileObject.Kind.SOURCE);
this.text = text;
}
@Override
public CharSequence getCharContent(boolean ignoreEncodingErrors) {
return text;
}
@Override
public boolean isNameCompatible(String simpleName, Kind kind) {
return true;
}
}
}