Top Description Fields Constructors Methods
jdk.internal.org.objectweb.asm.util

public final Class TraceClassVisitor

extends ClassVisitor
Class Inheritance
Imports
java.io.PrintWriter, jdk.internal.org.objectweb.asm.AnnotationVisitor, .Attribute, .ClassVisitor, .FieldVisitor, .MethodVisitor, .ModuleVisitor, .Opcodes, .RecordComponentVisitor, .TypePath
A ClassVisitor that prints the classes it visits with a Printer. This class visitor can be used in the middle of a class visitor chain to trace the class that is visited at a given point in this chain. This may be useful for debugging purposes.

When used with a Textifier, the trace printed when visiting the 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 Hello is defined by: 

public class Hello {

  public static void main(String[] args) {
    System.out.println("hello");
  }
}
Authors
Eric Bruneton, Eugene Kuleshov

Field Summary

Modifier and TypeField and Description
public final Printer
p

The printer to convert the visited class into text.

private final PrintWriter
printWriter

The print writer to be used to print the class.

Inherited from jdk.internal.org.objectweb.asm.ClassVisitor:
apicv

Constructor Summary

AccessConstructor and Description
public
TraceClassVisitor(final PrintWriter
the print writer to be used to print the class. May be null.
printWriter)

Constructs a new TraceClassVisitor.

public
TraceClassVisitor(final ClassVisitor
the class visitor to which to delegate calls. May be null.
classVisitor, final PrintWriter
the print writer to be used to print the class. May be null.
printWriter)

Constructs a new TraceClassVisitor.

public
TraceClassVisitor(final ClassVisitor
the class visitor to which to delegate calls. May be null.
classVisitor, final Printer
the printer to convert the visited class into text.
printer, final PrintWriter
the print writer to be used to print the class. May be null.
printWriter)

Constructs a new TraceClassVisitor.

Method Summary

Modifier and TypeMethod and Description
public void
visit(final int
the class version. The minor version is stored in the 16 most significant bits, and the major version in the 16 least significant bits.
version, final int
the class's access flags (see Opcodes). This parameter also indicates if the class is deprecated Opcodes#ACC_DEPRECATED or a record Opcodes#ACC_RECORD.
access, final String
the internal name of the class (see Type#getInternalName()).
name, final String
the signature of this class. May be null if the class is not a generic one, and does not extend or implement generic classes or interfaces.
signature, final String
the internal of name of the super class (see Type#getInternalName()). For interfaces, the super class is Object. May be null, but only for the Object class.
superName, final String[]
the internal names of the class's interfaces (see Type#getInternalName()). May be null.
interfaces)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visit.

Visits the header of the class.

public AnnotationVisitor
visitAnnotation(final String
the class descriptor of the annotation class.
descriptor, final boolean
true if the annotation is visible at runtime.
visible)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitAnnotation.

Visits an annotation of the class.

public void
visitAttribute(final Attribute
an attribute.
attribute)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitAttribute.

Visits a non standard attribute of the class.

public void
visitEnd()

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitEnd.

Visits the end of the class.

public FieldVisitor
visitField(final int
the field's access flags (see Opcodes). This parameter also indicates if the field is synthetic and/or deprecated.
access, final String
the field's name.
name, final String
the field's descriptor (see Type).
descriptor, final String
the field's signature. May be null if the field's type does not use generic types.
signature, final Object
the field's initial value. This parameter, which may be null if the field does not have an initial value, must be an Integer, a Float, a Long, a Double or a String (for int, float, long or String fields respectively). This parameter is only used for static fields. Its value is ignored for non static fields, which must be initialized through bytecode instructions in constructors or methods.
value)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitField.

Visits a field of the class.

public void
visitInnerClass(final String
the internal name of C (see Type#getInternalName()).
name, final String
the internal name of the class or interface C is a member of (see Type#getInternalName()). Must be null if C is not the member of a class or interface (e.g. for local or anonymous classes).
outerName, final String
the (simple) name of C. Must be null for anonymous inner classes.
innerName, final int
the access flags of C originally declared in the source code from which this class was compiled.
access)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitInnerClass.

Visits information about an inner class.

public MethodVisitor
visitMethod(final int
the method's access flags (see Opcodes). This parameter also indicates if the method is synthetic and/or deprecated.
access, final String
the method's name.
name, final String
the method's descriptor (see Type).
descriptor, final String
the method's signature. May be null if the method parameters, return type and exceptions do not use generic types.
signature, final String[]
the internal names of the method's exception classes (see Type#getInternalName()). May be null.
exceptions)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitMethod.

Visits a method of the class.

public ModuleVisitor
visitModule(final String
the fully qualified name (using dots) of the module.
name, final int
the module access flags, among ACC_OPEN, ACC_SYNTHETIC and ACC_MANDATED.
flags, final String
the module version, or null.
version)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitModule.

Visit the module corresponding to the class.

public void
visitNestHost(final String
the internal name of the host class of the nest (see Type#getInternalName()).
nestHost)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitNestHost.

Visits the nest host class of the class.

public void
visitNestMember(final String
the internal name of a nest member (see Type#getInternalName()).
nestMember)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitNestMember.

Visits a member of the nest.

public void
visitOuterClass(final String
internal name of the enclosing class of the class (see Type#getInternalName()).
owner, final String
the name of the method that contains the class, or null if the class is not enclosed in a method or constructor of its enclosing class (e.g. if it is enclosed in an instance initializer, static initializer, instance variable initializer, or class variable initializer).
name, final String
the descriptor of the method that contains the class, or null if the class is not enclosed in a method or constructor of its enclosing class (e.g. if it is enclosed in an instance initializer, static initializer, instance variable initializer, or class variable initializer).
descriptor)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitOuterClass.

Visits the enclosing class of the class.

public void
visitPermittedSubclass(final String
the internal name of a permitted subclass (see Type#getInternalName()).
permittedSubclass)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitPermittedSubclass.

Visits a permitted subclasses.

public RecordComponentVisitor
visitRecordComponent(final String
the record component name.
name, final String
the record component descriptor (see Type).
descriptor, final String
the record component signature. May be null if the record component type does not use generic types.
signature)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitRecordComponent.

Visits a record component of the class.

public void
visitSource(final String
the name of the source file from which the class was compiled. May be null.
file, final String
additional debug information to compute the correspondence between source and compiled elements of the class. May be null.
debug)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitSource.

Visits the source of the class.

public AnnotationVisitor
visitTypeAnnotation(final int
a reference to the annotated type. The sort of this type reference must be TypeReference#CLASS_TYPE_PARAMETER, TypeReference#CLASS_TYPE_PARAMETER_BOUND or TypeReference#CLASS_EXTENDS. See TypeReference.
typeRef, final TypePath
the path to the annotated type argument, wildcard bound, array element type, or static inner type within 'typeRef'. May be null if the annotation targets 'typeRef' as a whole.
typePath, final String
the class descriptor of the annotation class.
descriptor, final boolean
true if the annotation is visible at runtime.
visible)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitTypeAnnotation.

Visits an annotation on a type in the class signature.

Inherited from jdk.internal.org.objectweb.asm.ClassVisitor:
getDelegate

Field Detail

pback to summary
public final Printer p

The printer to convert the visited class into text.

printWriterback to summary
private final PrintWriter printWriter

The print writer to be used to print the class. May be null.

Constructor Detail

TraceClassVisitorback to summary
public TraceClassVisitor(final PrintWriter printWriter)

Constructs a new TraceClassVisitor.

Parameters
printWriter:PrintWriter

the print writer to be used to print the class. May be null.

TraceClassVisitorback to summary
public TraceClassVisitor(final ClassVisitor classVisitor, final PrintWriter printWriter)

Constructs a new TraceClassVisitor.

Parameters
classVisitor:ClassVisitor

the class visitor to which to delegate calls. May be null.

printWriter:PrintWriter

the print writer to be used to print the class. May be null.

TraceClassVisitorback to summary
public TraceClassVisitor(final ClassVisitor classVisitor, final Printer printer, final PrintWriter printWriter)

Constructs a new TraceClassVisitor.

Parameters
classVisitor:ClassVisitor

the class visitor to which to delegate calls. May be null.

printer:Printer

the printer to convert the visited class into text.

printWriter:PrintWriter

the print writer to be used to print the class. May be null.

Method Detail

visitback to summary
public void visit(final int version, final int access, final String name, final String signature, final String superName, final String[] interfaces)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visit.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visit.

Visits the header of the class.

Parameters
version:int

the class version. The minor version is stored in the 16 most significant bits, and the major version in the 16 least significant bits.

access:int

the class's access flags (see Opcodes). This parameter also indicates if the class is deprecated Opcodes#ACC_DEPRECATED or a record Opcodes#ACC_RECORD.

name:String

the internal name of the class (see Type#getInternalName()).

signature:String

the signature of this class. May be null if the class is not a generic one, and does not extend or implement generic classes or interfaces.

superName:String

the internal of name of the super class (see Type#getInternalName()). For interfaces, the super class is Object. May be null, but only for the Object class.

interfaces:String[]

the internal names of the class's interfaces (see Type#getInternalName()). May be null.

Annotations
@Override
visitAnnotationback to summary
public AnnotationVisitor visitAnnotation(final String descriptor, final boolean visible)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitAnnotation.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitAnnotation.

Visits an annotation of the class.

Parameters
descriptor:String

the class descriptor of the annotation class.

visible:boolean

true if the annotation is visible at runtime.

Returns:AnnotationVisitor

a visitor to visit the annotation values, or null if this visitor is not interested in visiting this annotation.

Annotations
@Override
visitAttributeback to summary
public void visitAttribute(final Attribute attribute)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitAttribute.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitAttribute.

Visits a non standard attribute of the class.

Parameters
attribute:Attribute

an attribute.

Annotations
@Override
visitEndback to summary
public void visitEnd()

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitEnd.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitEnd.

Visits the end of the class. This method, which is the last one to be called, is used to inform the visitor that all the fields and methods of the class have been visited.

Annotations
@Override
visitFieldback to summary
public FieldVisitor visitField(final int access, final String name, final String descriptor, final String signature, final Object value)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitField.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitField.

Visits a field of the class.

Parameters
access:int

the field's access flags (see Opcodes). This parameter also indicates if the field is synthetic and/or deprecated.

name:String

the field's name.

descriptor:String

the field's descriptor (see Type).

signature:String

the field's signature. May be null if the field's type does not use generic types.

value:Object

the field's initial value. This parameter, which may be null if the field does not have an initial value, must be an Integer, a Float, a Long, a Double or a String (for int, float, long or String fields respectively). This parameter is only used for static fields. Its value is ignored for non static fields, which must be initialized through bytecode instructions in constructors or methods.

Returns:FieldVisitor

a visitor to visit field annotations and attributes, or null if this class visitor is not interested in visiting these annotations and attributes.

Annotations
@Override
visitInnerClassback to summary
public void visitInnerClass(final String name, final String outerName, final String innerName, final int access)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitInnerClass.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitInnerClass.

Visits information about an inner class. This inner class is not necessarily a member of the class being visited. More precisely, every class or interface C which is referenced by this class and which is not a package member must be visited with this method. This class must reference its nested class or interface members, and its enclosing class, if any. See the JVMS 4.7.6 section for more details.

Parameters
name:String

the internal name of C (see Type#getInternalName()).

outerName:String

the internal name of the class or interface C is a member of (see Type#getInternalName()). Must be null if C is not the member of a class or interface (e.g. for local or anonymous classes).

innerName:String

the (simple) name of C. Must be null for anonymous inner classes.

access:int

the access flags of C originally declared in the source code from which this class was compiled.

Annotations
@Override
visitMethodback to summary
public MethodVisitor visitMethod(final int access, final String name, final String descriptor, final String signature, final String[] exceptions)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitMethod.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitMethod.

Visits a method of the class. This method must return a new MethodVisitor instance (or null) each time it is called, i.e., it should not return a previously returned visitor.

Parameters
access:int

the method's access flags (see Opcodes). This parameter also indicates if the method is synthetic and/or deprecated.

name:String

the method's name.

descriptor:String

the method's descriptor (see Type).

signature:String

the method's signature. May be null if the method parameters, return type and exceptions do not use generic types.

exceptions:String[]

the internal names of the method's exception classes (see Type#getInternalName()). May be null.

Returns:MethodVisitor

an object to visit the byte code of the method, or null if this class visitor is not interested in visiting the code of this method.

Annotations
@Override
visitModuleback to summary
public ModuleVisitor visitModule(final String name, final int flags, final String version)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitModule.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitModule.

Visit the module corresponding to the class.

Parameters
name:String

the fully qualified name (using dots) of the module.

flags:int

the module access flags, among ACC_OPEN, ACC_SYNTHETIC and ACC_MANDATED.

version:String

the module version, or null.

Returns:ModuleVisitor

a visitor to visit the module values, or null if this visitor is not interested in visiting this module.

Annotations
@Override
visitNestHostback to summary
public void visitNestHost(final String nestHost)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitNestHost.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitNestHost.

Visits the nest host class of the class. A nest is a set of classes of the same package that share access to their private members. One of these classes, called the host, lists the other members of the nest, which in turn should link to the host of their nest. This method must be called only once and only if the visited class is a non-host member of a nest. A class is implicitly its own nest, so it's invalid to call this method with the visited class name as argument.

Parameters
nestHost:String

the internal name of the host class of the nest (see Type#getInternalName()).

Annotations
@Override
visitNestMemberback to summary
public void visitNestMember(final String nestMember)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitNestMember.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitNestMember.

Visits a member of the nest. A nest is a set of classes of the same package that share access to their private members. One of these classes, called the host, lists the other members of the nest, which in turn should link to the host of their nest. This method must be called only if the visited class is the host of a nest. A nest host is implicitly a member of its own nest, so it's invalid to call this method with the visited class name as argument.

Parameters
nestMember:String

the internal name of a nest member (see Type#getInternalName()).

Annotations
@Override
visitOuterClassback to summary
public void visitOuterClass(final String owner, final String name, final String descriptor)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitOuterClass.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitOuterClass.

Visits the enclosing class of the class. This method must be called only if this class is a local or anonymous class. See the JVMS 4.7.7 section for more details.

Parameters
owner:String

internal name of the enclosing class of the class (see Type#getInternalName()).

name:String

the name of the method that contains the class, or null if the class is not enclosed in a method or constructor of its enclosing class (e.g. if it is enclosed in an instance initializer, static initializer, instance variable initializer, or class variable initializer).

descriptor:String

the descriptor of the method that contains the class, or null if the class is not enclosed in a method or constructor of its enclosing class (e.g. if it is enclosed in an instance initializer, static initializer, instance variable initializer, or class variable initializer).

Annotations
@Override
visitPermittedSubclassback to summary
public void visitPermittedSubclass(final String permittedSubclass)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitPermittedSubclass.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitPermittedSubclass.

Visits a permitted subclasses. A permitted subclass is one of the allowed subclasses of the current class.

Parameters
permittedSubclass:String

the internal name of a permitted subclass (see Type#getInternalName()).

Annotations
@Override
visitRecordComponentback to summary
public RecordComponentVisitor visitRecordComponent(final String name, final String descriptor, final String signature)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitRecordComponent.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitRecordComponent.

Visits a record component of the class.

Parameters
name:String

the record component name.

descriptor:String

the record component descriptor (see Type).

signature:String

the record component signature. May be null if the record component type does not use generic types.

Returns:RecordComponentVisitor

a visitor to visit this record component annotations and attributes, or null if this class visitor is not interested in visiting these annotations and attributes.

Annotations
@Override
visitSourceback to summary
public void visitSource(final String file, final String debug)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitSource.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitSource.

Visits the source of the class.

Parameters
file:String

the name of the source file from which the class was compiled. May be null.

debug:String

additional debug information to compute the correspondence between source and compiled elements of the class. May be null.

Annotations
@Override
visitTypeAnnotationback to summary
public AnnotationVisitor visitTypeAnnotation(final int typeRef, final TypePath typePath, final String descriptor, final boolean visible)

Overrides jdk.internal.org.objectweb.asm.ClassVisitor.visitTypeAnnotation.

Doc from jdk.internal.org.objectweb.asm.ClassVisitor.visitTypeAnnotation.

Visits an annotation on a type in the class signature.

Parameters
typeRef:int

a reference to the annotated type. The sort of this type reference must be TypeReference#CLASS_TYPE_PARAMETER, TypeReference#CLASS_TYPE_PARAMETER_BOUND or TypeReference#CLASS_EXTENDS. See TypeReference.

typePath:TypePath

the path to the annotated type argument, wildcard bound, array element type, or static inner type within 'typeRef'. May be null if the annotation targets 'typeRef' as a whole.

descriptor:String

the class descriptor of the annotation class.

visible:boolean

true if the annotation is visible at runtime.

Returns:AnnotationVisitor

a visitor to visit the annotation values, or null if this visitor is not interested in visiting this annotation.

Annotations
@Override