When used with a {@link Textifier}, the trace printed when visiting the {@code Hello} class is * the following: * *
* // class version 49.0 (49) // access flags 0x21 public class Hello {
*
* // compiled from: Hello.java
*
* // access flags 0x1
* public <init> ()V
* ALOAD 0
* INVOKESPECIAL java/lang/Object <init> ()V
* RETURN
* MAXSTACK = 1 MAXLOCALS = 1
*
* // access flags 0x9
* public static main ([Ljava/lang/String;)V
* GETSTATIC java/lang/System out Ljava/io/PrintStream;
* LDC "hello"
* INVOKEVIRTUAL java/io/PrintStream println (Ljava/lang/String;)V
* RETURN
* MAXSTACK = 2 MAXLOCALS = 1
* }
*
*
* where {@code Hello} is defined by: * *
* public class Hello {
*
* public static void main(String[] args) {
* System.out.println("hello");
* }
* }
*
*
* @author Eric Bruneton
* @author Eugene Kuleshov
*/
public final class TraceClassVisitor extends ClassVisitor {
/** The print writer to be used to print the class. May be {@literal null}. */
private final PrintWriter printWriter;
/** The printer to convert the visited class into text. */
// DontCheck(MemberName): can't be renamed (for backward binary compatibility).
public final Printer p;
/**
* Constructs a new {@link TraceClassVisitor}.
*
* @param printWriter the print writer to be used to print the class. May be {@literal null}.
*/
public TraceClassVisitor(final PrintWriter printWriter) {
this(null, printWriter);
}
/**
* Constructs a new {@link TraceClassVisitor}.
*
* @param classVisitor the class visitor to which to delegate calls. May be {@literal null}.
* @param printWriter the print writer to be used to print the class. May be {@literal null}.
*/
public TraceClassVisitor(final ClassVisitor classVisitor, final PrintWriter printWriter) {
this(classVisitor, new Textifier(), printWriter);
}
/**
* Constructs a new {@link TraceClassVisitor}.
*
* @param classVisitor the class visitor to which to delegate calls. May be {@literal null}.
* @param printer the printer to convert the visited class into text.
* @param printWriter the print writer to be used to print the class. May be {@literal null}.
*/
public TraceClassVisitor(
final ClassVisitor classVisitor, final Printer printer, final PrintWriter printWriter) {
super(/* latest api = */ Opcodes.ASM10_EXPERIMENTAL, classVisitor);
this.printWriter = printWriter;
this.p = printer;
}
@Override
public void visit(
final int version,
final int access,
final String name,
final String signature,
final String superName,
final String[] interfaces) {
p.visit(version, access, name, signature, superName, interfaces);
super.visit(version, access, name, signature, superName, interfaces);
}
@Override
public void visitSource(final String file, final String debug) {
p.visitSource(file, debug);
super.visitSource(file, debug);
}
@Override
public ModuleVisitor visitModule(final String name, final int flags, final String version) {
Printer modulePrinter = p.visitModule(name, flags, version);
return new TraceModuleVisitor(super.visitModule(name, flags, version), modulePrinter);
}
@Override
public void visitNestHost(final String nestHost) {
p.visitNestHost(nestHost);
super.visitNestHost(nestHost);
}
@Override
public void visitOuterClass(final String owner, final String name, final String descriptor) {
p.visitOuterClass(owner, name, descriptor);
super.visitOuterClass(owner, name, descriptor);
}
@Override
public AnnotationVisitor visitAnnotation(final String descriptor, final boolean visible) {
Printer annotationPrinter = p.visitClassAnnotation(descriptor, visible);
return new TraceAnnotationVisitor(
super.visitAnnotation(descriptor, visible), annotationPrinter);
}
@Override
public AnnotationVisitor visitTypeAnnotation(
final int typeRef, final TypePath typePath, final String descriptor, final boolean visible) {
Printer annotationPrinter = p.visitClassTypeAnnotation(typeRef, typePath, descriptor, visible);
return new TraceAnnotationVisitor(
super.visitTypeAnnotation(typeRef, typePath, descriptor, visible), annotationPrinter);
}
@Override
public void visitAttribute(final Attribute attribute) {
p.visitClassAttribute(attribute);
super.visitAttribute(attribute);
}
@Override
public void visitNestMember(final String nestMember) {
p.visitNestMember(nestMember);
super.visitNestMember(nestMember);
}
@Override
public void visitPermittedSubclass(final String permittedSubclass) {
p.visitPermittedSubclass(permittedSubclass);
super.visitPermittedSubclass(permittedSubclass);
}
@Override
public void visitInnerClass(
final String name, final String outerName, final String innerName, final int access) {
p.visitInnerClass(name, outerName, innerName, access);
super.visitInnerClass(name, outerName, innerName, access);
}
@Override
public RecordComponentVisitor visitRecordComponent(
final String name, final String descriptor, final String signature) {
Printer recordComponentPrinter = p.visitRecordComponent(name, descriptor, signature);
return new TraceRecordComponentVisitor(
super.visitRecordComponent(name, descriptor, signature), recordComponentPrinter);
}
@Override
public FieldVisitor visitField(
final int access,
final String name,
final String descriptor,
final String signature,
final Object value) {
Printer fieldPrinter = p.visitField(access, name, descriptor, signature, value);
return new TraceFieldVisitor(
super.visitField(access, name, descriptor, signature, value), fieldPrinter);
}
@Override
public MethodVisitor visitMethod(
final int access,
final String name,
final String descriptor,
final String signature,
final String[] exceptions) {
Printer methodPrinter = p.visitMethod(access, name, descriptor, signature, exceptions);
return new TraceMethodVisitor(
super.visitMethod(access, name, descriptor, signature, exceptions), methodPrinter);
}
@Override
public void visitEnd() {
p.visitClassEnd();
if (printWriter != null) {
p.print(printWriter);
printWriter.flush();
}
super.visitEnd();
}
}