Module openj9.dtfj

Package com.ibm.j9ddr.vm29.view.dtfj.java

Class DTFJJavaStackFrame

java.lang.Object

com.ibm.j9ddr.vm29.view.dtfj.java.DTFJJavaStackFrame

All Implemented Interfaces:

JavaLocation, JavaStackFrame

public class DTFJJavaStackFrame
extends Object
implements JavaStackFrame, JavaLocation

Combined JavaStackFrame & JavaLocation

Constructor Summary

Constructors

Constructor	Description
DTFJJavaStackFrame(DTFJJavaThread dtfjJavaThread, DTFJJavaMethod dtfjMethod, com.ibm.j9ddr.vm29.pointer.generated.J9MethodPointer method, ImagePointer pc, ImagePointer basePointer, U8Pointer bytecodePCOffset, boolean jitted)

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object obj)	Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison.
ImagePointer	getAddress()	Fetches the absolute address of the code which this location represents.
ImagePointer	getBasePointer()	Get a pointer to the base of this stack frame
int	getCompilationLevel()	Get the compilation level for this location.
String	getFilename()	Get the source file name.
Iterator	getHeapRoots()	Get the set of object roots from this stack frame.
int	getLineNumber()	Get the line number.
JavaLocation	getLocation()	Get the location at which the method owning this frame is currently executing
JavaMethod	getMethod()	Get the method which contains the point of execution.
int	hashCode()	Answers an integer hash code for the receiver.
String	toString()	Answers a string containing a concise, human-readable description of the receiver.

Methods declared in class java.lang.Object

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

Constructor Details

DTFJJavaStackFrame

public DTFJJavaStackFrame(DTFJJavaThread dtfjJavaThread,
 DTFJJavaMethod dtfjMethod,
 com.ibm.j9ddr.vm29.pointer.generated.J9MethodPointer method,
 ImagePointer pc,
 ImagePointer basePointer,
 U8Pointer bytecodePCOffset,
 boolean jitted)

Method Details

getBasePointer

public ImagePointer getBasePointer()
                            throws CorruptDataException

Description copied from interface: JavaStackFrame

Get a pointer to the base of this stack frame

Specified by:

getBasePointer in interface JavaStackFrame

Returns:

the base pointer of the stack frame

Throws:

CorruptDataException

getHeapRoots

public Iterator getHeapRoots()

Description copied from interface: JavaStackFrame

Get the set of object roots from this stack frame.

Specified by:

getHeapRoots in interface JavaStackFrame

Returns:

an iterator of JavaReferences

getLocation

public JavaLocation getLocation()
                         throws CorruptDataException

Description copied from interface: JavaStackFrame

Get the location at which the method owning this frame is currently executing

Specified by:

getLocation in interface JavaStackFrame

Returns:

a location object describing where the frame is executing

Throws:

CorruptDataException

See Also:

• JavaLocation

getAddress

public ImagePointer getAddress()
                        throws CorruptDataException

Description copied from interface: JavaLocation

Fetches the absolute address of the code which this location represents. This pointer will be contained within one of the segments returned by getBytecodeSections() or getCompiledSections() of the method returned by getMethod().

null may be returned, particularly for methods with no bytecode or compiled sections (e.g. some native methods)

Although an offset into the method may be calculated using this pointer, caution should be exercised in attempting to map this offset to an offset within the original class file. Various transformations may have been applied to the bytecodes by the VM or other agents which may make the offset difficult to interpret.

For native methods, the address may be meaningless.

Specified by:

getAddress in interface JavaLocation

Returns:

the address in memory of the managed code

Throws:

CorruptDataException

getCompilationLevel

public int getCompilationLevel()
                        throws CorruptDataException

Description copied from interface: JavaLocation

Get the compilation level for this location. This is an implementation defined number indicating the level at which the current location was compiled. 0 indicates interpreted. Any positive number indicates some level of JIT compilation. Typically, higher numbers indicate more aggressive compilation strategies

For native methods, a non-zero compilation level indicates that some level of JIT compilation has been applied to the native call (e.g. a custom native call stub). To determine if the method is native, use getMethod().getModifiers().

Specified by:

getCompilationLevel in interface JavaLocation

Returns:

the compilation level

Throws:

CorruptDataException

getFilename

public String getFilename()
                   throws DataUnavailable,
CorruptDataException

Description copied from interface: JavaLocation

Get the source file name.

Specified by:

getFilename in interface JavaLocation

Returns:

the name of the source file, if available, or throws DataUnavailable if it is not available

Throws:

DataUnavailable - if the source file name is unavailable in the core

CorruptDataException

getLineNumber

public int getLineNumber()
                  throws DataUnavailable,
CorruptDataException

Description copied from interface: JavaLocation

Get the line number.

Specified by:

getLineNumber in interface JavaLocation

Returns:

the line number, if available, or throws DataUnavailable if it is not available Line numbers are counted from 1

Throws:

DataUnavailable - if the line number data is not available for this location

CorruptDataException

getMethod

public JavaMethod getMethod()
                     throws CorruptDataException

Description copied from interface: JavaLocation

Get the method which contains the point of execution.

Specified by:

getMethod in interface JavaLocation

Returns:

the method which contains the point of execution

Throws:

CorruptDataException

equals

public boolean equals(Object obj)

Description copied from class: java.lang.Object

Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison. The implementation in Object answers true only if the argument is the exact same object as the receiver (==).

Specified by:

equals in interface JavaLocation

Specified by:

equals in interface JavaStackFrame

Overrides:

equals in class Object

Parameters:

obj - Object the object to compare with this object.

Returns:

boolean true if the object is the same as this object false if it is different from this object.

See Also:

• Object.hashCode()

hashCode

public int hashCode()

Description copied from class: java.lang.Object

Answers an integer hash code for the receiver. Any two objects which answer true when passed to .equals must answer the same value for this method.

Specified by:

hashCode in interface JavaLocation

Specified by:

hashCode in interface JavaStackFrame

Overrides:

hashCode in class Object

Returns:

the receiver's hash.

See Also:

• Object.equals(java.lang.Object)

toString

public String toString()

Description copied from class: java.lang.Object

Answers a string containing a concise, human-readable description of the receiver.

Specified by:

toString in interface JavaLocation

Overrides:

toString in class Object

Returns:

String a printable representation for the receiver.