public class TraceClassVisitor extends TraceAbstractVisitor implements ClassVisitor
ClassVisitor that prints a disassembled view of the classes it
visits. This class visitor can be used alone (see the main
method) to disassemble a class. It can also be used in the middle of class
visitor chain to trace the class that is visited at a given point in this
chain. This may be uselful for debugging purposes. The trace printed when visiting the Hello class is the following:
// class version 49.0 (49)
// access flags 33
public class Hello {
// compiled from: Hello.java
// access flags 1
public <init> ()V
ALOAD 0
INVOKESPECIAL java/lang/Object <init> ()V
RETURN
MAXSTACK = 1
MAXLOCALS = 1
// access flags 9
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");
}
}
| Modifier and Type | Field and Description |
|---|---|
protected ClassVisitor |
cv
The
ClassVisitor to which this visitor delegates calls. |
protected PrintWriter |
pw
The print writer to be used to print the class.
|
CLASS_DECLARATION, CLASS_SIGNATURE, FIELD_DESCRIPTOR, FIELD_SIGNATURE, INTERNAL_NAME, METHOD_DESCRIPTOR, METHOD_SIGNATURE, PARAMETERS_DECLARATION, tab, TYPE_DECLARATIONbuf, OPCODES, text, TYPES| Constructor and Description |
|---|
TraceClassVisitor(ClassVisitor cv,
PrintWriter pw)
Constructs a new
TraceClassVisitor. |
TraceClassVisitor(PrintWriter pw)
Constructs a new
TraceClassVisitor. |
| Modifier and Type | Method and Description |
|---|---|
protected TraceFieldVisitor |
createTraceFieldVisitor() |
protected TraceMethodVisitor |
createTraceMethodVisitor() |
static void |
main(String[] args)
Prints a disassembled view of the given class to the standard output.
|
void |
visit(int version,
int access,
String name,
String signature,
String superName,
String[] interfaces)
Visits the header of the class.
|
AnnotationVisitor |
visitAnnotation(String desc,
boolean visible)
Prints a disassembled view of the given annotation.
|
void |
visitAttribute(Attribute attr)
Prints a disassembled view of the given attribute.
|
void |
visitEnd()
Does nothing.
|
FieldVisitor |
visitField(int access,
String name,
String desc,
String signature,
Object value)
Visits a field of the class.
|
void |
visitInnerClass(String name,
String outerName,
String innerName,
int access)
Visits information about an inner class.
|
MethodVisitor |
visitMethod(int access,
String name,
String desc,
String signature,
String[] exceptions)
Visits a method of the class.
|
void |
visitOuterClass(String owner,
String name,
String desc)
Visits the enclosing class of the class.
|
void |
visitSource(String file,
String debug)
Visits the source of the class.
|
appendDescriptor, createTraceAnnotationVisitorappendString, getDefaultAttributes, getText, printprotected final ClassVisitor cv
ClassVisitor to which this visitor delegates calls. May be
null.protected final PrintWriter pw
public TraceClassVisitor(PrintWriter pw)
TraceClassVisitor.pw - the print writer to be used to print the class.public TraceClassVisitor(ClassVisitor cv, PrintWriter pw)
TraceClassVisitor.cv - the ClassVisitor to which this visitor delegates calls.
May be null.pw - the print writer to be used to print the class.public static void main(String[] args) throws Exception
Usage: TraceClassVisitor [-debug] <fully qualified class name or class file name >
args - the command line arguments.Exception - if the class cannot be found, or if an IO exception
occurs.public void visit(int version,
int access,
String name,
String signature,
String superName,
String[] interfaces)
ClassVisitorvisit in interface ClassVisitorversion - the class version.access - the class's access flags (see Opcodes). This
parameter also indicates if the class is deprecated.name - the internal name of the class (see
getInternalName).signature - 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 - the internal of name of the super class (see
getInternalName). For interfaces,
the super class is Object. May be null, but
only for the Object class.interfaces - the internal names of the class's interfaces (see
getInternalName). May be
null.public void visitSource(String file, String debug)
ClassVisitorvisitSource in interface ClassVisitorfile - the name of the source file from which the class was
compiled. May be null.debug - additional debug information to compute the correspondance
between source and compiled elements of the class. May be
null.public void visitOuterClass(String owner, String name, String desc)
ClassVisitorvisitOuterClass in interface ClassVisitorowner - internal name of the enclosing class of the class.name - the name of the method that contains the class, or
null if the class is not enclosed in a method of its
enclosing class.desc - the descriptor of the method that contains the class, or
null if the class is not enclosed in a method of its
enclosing class.public AnnotationVisitor visitAnnotation(String desc, boolean visible)
TraceAbstractVisitorvisitAnnotation in interface ClassVisitorvisitAnnotation in class TraceAbstractVisitordesc - the class descriptor of the annotation class.visible - true if the annotation is visible at runtime.public void visitAttribute(Attribute attr)
TraceAbstractVisitorvisitAttribute in interface ClassVisitorvisitAttribute in class TraceAbstractVisitorattr - an attribute.public void visitInnerClass(String name, String outerName, String innerName, int access)
ClassVisitorvisitInnerClass in interface ClassVisitorname - the internal name of an inner class (see
getInternalName).outerName - the internal name of the class to which the inner class
belongs (see getInternalName). May
be null for not member classes.innerName - the (simple) name of the inner class inside its
enclosing class. May be null for anonymous inner
classes.access - the access flags of the inner class as originally declared
in the enclosing class.public FieldVisitor visitField(int access, String name, String desc, String signature, Object value)
ClassVisitorvisitField in interface ClassVisitoraccess - the field's access flags (see Opcodes). This
parameter also indicates if the field is synthetic and/or
deprecated.name - the field's name.desc - the field's descriptor (see Type).signature - the field's signature. May be null if the
field's type does not use generic types.value - 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.public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions)
ClassVisitorMethodVisitor instance (or null) each time it is
called, i.e., it should not return a previously returned visitor.visitMethod in interface ClassVisitoraccess - the method's access flags (see Opcodes). This
parameter also indicates if the method is synthetic and/or
deprecated.name - the method's name.desc - the method's descriptor (see Type).signature - the method's signature. May be null if the
method parameters, return type and exceptions do not use generic
types.exceptions - the internal names of the method's exception classes
(see getInternalName). May be
null.public void visitEnd()
TraceAbstractVisitorvisitEnd in interface ClassVisitorvisitEnd in class TraceAbstractVisitorprotected TraceFieldVisitor createTraceFieldVisitor()
protected TraceMethodVisitor createTraceMethodVisitor()
Copyright © 2018. All rights reserved.