Class StackMapTable

java.lang.Object

javassist.bytecode.AttributeInfo

javassist.bytecode.StackMapTable

public class StackMapTable
extends AttributeInfo

stack_map attribute.

This is an entry in the attributes table of a Code attribute. It was introduced by J2SE 6 for the verification by typechecking.

Since:

3.4

See Also:

• StackMap

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	StackMapTable.RuntimeCopyException	An exception that may be thrown by copy() in StackMapTable.
static class	StackMapTable.Walker	A code walker for a StackMapTable attribute.
static class	StackMapTable.Writer	A writer of stack map tables.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DOUBLE	Double_variable_info.tag.
static final int	FLOAT	Float_variable_info.tag.
static final int	INTEGER	Integer_variable_info.tag.
static final int	LONG	Long_variable_info.tag.
static final int	NULL	Null_variable_info.tag.
static final int	OBJECT	Object_variable_info.tag.
static final String	tag	The name of this attribute "StackMapTable".
static final int	THIS	UninitializedThis_variable_info.tag.
static final int	TOP	Top_variable_info.tag.
static final int	UNINIT	Uninitialized_variable_info.tag.

Method Summary

Modifier and Type	Method	Description
AttributeInfo	copy(ConstPool newCp, Map<String,String> classnames)	Makes a copy.
void	insertLocal(int index, int tag, int classInfo)	Updates this stack map table when a new local variable is inserted for a new parameter.
void	println(PrintStream ps)	Prints the stack table map.
void	println(PrintWriter w)	Prints the stack table map.
void	removeNew(int where)	Undocumented method.
static int	typeTagOf(char descriptor)	Returns the tag of the type specified by the descriptor.

Methods inherited from class AttributeInfo

get, getConstPool, getName, length, set

Methods inherited from class Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

tag

public static final String tag

The name of this attribute "StackMapTable".

See Also:

• Constant Field Values

TOP

public static final int TOP

Top_variable_info.tag.

See Also:

• Constant Field Values

INTEGER

public static final int INTEGER

Integer_variable_info.tag.

See Also:

• Constant Field Values

FLOAT

public static final int FLOAT

Float_variable_info.tag.

See Also:

• Constant Field Values

DOUBLE

public static final int DOUBLE

Double_variable_info.tag.

See Also:

• Constant Field Values

LONG

public static final int LONG

Long_variable_info.tag.

See Also:

• Constant Field Values

NULL

public static final int NULL

Null_variable_info.tag.

See Also:

• Constant Field Values

THIS

public static final int THIS

UninitializedThis_variable_info.tag.

See Also:

• Constant Field Values

OBJECT

public static final int OBJECT

Object_variable_info.tag.

See Also:

• Constant Field Values

UNINIT

public static final int UNINIT

Uninitialized_variable_info.tag.

See Also:

• Constant Field Values

Method Details

copy

public AttributeInfo copy(ConstPool newCp,
 Map<String,String> classnames)
                   throws StackMapTable.RuntimeCopyException

Makes a copy.

Overrides:

copy in class AttributeInfo

Parameters:

newCp - the constant pool table used by the new copy.

classnames - pairs of replaced and substituted class names.

Throws:

StackMapTable.RuntimeCopyException - if a BadBytecode exception is thrown while copying, it is converted into RuntimeCopyException.

insertLocal

public void insertLocal(int index,
 int tag,
 int classInfo)
                 throws BadBytecode

Updates this stack map table when a new local variable is inserted for a new parameter.

Parameters:

index - the index of the added local variable.

tag - the type tag of that local variable.

classInfo - the index of the CONSTANT_Class_info structure in a constant pool table. This should be zero unless the tag is ITEM_Object.

Throws:

BadBytecode

See Also:

• CtBehavior.addParameter(javassist.CtClass)
• typeTagOf(char)
• ConstPool

typeTagOf

public static int typeTagOf(char descriptor)

Returns the tag of the type specified by the descriptor. This method returns INTEGER unless the descriptor is either D (double), F (float), J (long), L (class type), or [ (array).

Parameters:

descriptor - the type descriptor.

See Also:

• Descriptor

println

public void println(PrintWriter w)

Prints the stack table map.

println

public void println(PrintStream ps)

Prints the stack table map.

Parameters:

ps - a print stream such as System.out.

removeNew

public void removeNew(int where)
               throws CannotCompileException

Undocumented method. Do not use; internal-use only.

This method is for javassist.convert.TransformNew. It is called to update the stack map table when the NEW opcode (and the following DUP) is removed.

Parameters:

where - the position of the removed NEW opcode.

Throws:

CannotCompileException