JavaTM 2 Platform Std. Ed. v1.6.0
java.lang
Class StackTraceElement
java.lang.Object
java.lang.StackTraceElement
- All Implemented Interfaces:
- Serializable
public final class StackTraceElement - extends Object
- implements Serializable
An element in a stack trace, as returned by Throwable.getStackTrace() . Each element represents a single stack frame.
All stack frames except for the one at the top of the stack represent
a method invocation. The frame at the top of the stack represents the
execution point at which the stack trace was generated. Typically,
this is the point at which the throwable corresponding to the stack trace
was created.
- Since:
- 1.4
- See Also:
- Serialized Form
Constructor Summary |
StackTraceElement(String declaringClass,
String methodName,
String fileName,
int lineNumber)
Creates a stack trace element representing the specified execution
point. |
Method Summary |
boolean |
equals(Object obj)
Returns true if the specified object is another
StackTraceElement instance representing the same execution
point as this instance. |
String |
getClassName()
Returns the fully qualified name of the class containing the
execution point represented by this stack trace element. |
String |
getFileName()
Returns the name of the source file containing the execution point
represented by this stack trace element. |
int |
getLineNumber()
Returns the line number of the source line containing the execution
point represented by this stack trace element. |
String |
getMethodName()
Returns the name of the method containing the execution point
represented by this stack trace element. |
int |
hashCode()
Returns a hash code value for this stack trace element. |
boolean |
isNativeMethod()
Returns true if the method containing the execution point
represented by this stack trace element is a native method. |
String |
toString()
Returns a string representation of this stack trace element. |
StackTraceElement
public StackTraceElement(String declaringClass,
String methodName,
String fileName,
int lineNumber)
- Creates a stack trace element representing the specified execution
point.
- Parameters:
declaringClass - the fully qualified name of the class containing
the execution point represented by the stack trace elementmethodName - the name of the method containing the execution point
represented by the stack trace elementfileName - the name of the file containing the execution point
represented by the stack trace element, or null if
this information is unavailablelineNumber - the line number of the source line containing the
execution point represented by this stack trace element, or
a negative number if this information is unavailable. A value
of -2 indicates that the method containing the execution point
is a native method
- Throws:
NullPointerException - if declaringClass or
methodName is null- Since:
- 1.5
getFileName
public String getFileName()
- Returns the name of the source file containing the execution point
represented by this stack trace element. Generally, this corresponds
to the SourceFile attribute of the relevant class
file (as per The Java Virtual Machine Specification, Section
4.7.7). In some systems, the name may refer to some source code unit
other than a file, such as an entry in source repository.
- Returns:
- the name of the file containing the execution point
represented by this stack trace element, or null if
this information is unavailable.
getLineNumber
public int getLineNumber()
- Returns the line number of the source line containing the execution
point represented by this stack trace element. Generally, this is
derived from the LineNumberTable attribute of the relevant
class file (as per The Java Virtual Machine
Specification, Section 4.7.8).
- Returns:
- the line number of the source line containing the execution
point represented by this stack trace element, or a negative
number if this information is unavailable.
getClassName
public String getClassName()
- Returns the fully qualified name of the class containing the
execution point represented by this stack trace element.
- Returns:
- the fully qualified name of the Class containing
the execution point represented by this stack trace element.
getMethodName
public String getMethodName()
- Returns the name of the method containing the execution point
represented by this stack trace element. If the execution point is
contained in an instance or class initializer, this method will return
the appropriate special method name, <init> or
<clinit>, as per Section 3.9 of The Java Virtual
Machine Specification.
- Returns:
- the name of the method containing the execution point
represented by this stack trace element.
isNativeMethod
public boolean isNativeMethod()
- Returns true if the method containing the execution point
represented by this stack trace element is a native method.
- Returns:
- true if the method containing the execution point
represented by this stack trace element is a native method.
toString
public String toString()
- Returns a string representation of this stack trace element. The
format of this string depends on the implementation, but the following
examples may be regarded as typical:
-
"MyClass.mash(MyClass.java:9)" - Here, "MyClass"
is the fully-qualified name of the class containing the
execution point represented by this stack trace element,
"mash" is the name of the method containing the execution
point, "MyClass.java" is the source file containing the
execution point, and "9" is the line number of the source
line containing the execution point.
-
"MyClass.mash(MyClass.java)" - As above, but the line
number is unavailable.
-
"MyClass.mash(Unknown Source)" - As above, but neither
the file name nor the line number are available.
-
"MyClass.mash(Native Method)" - As above, but neither
the file name nor the line number are available, and the method
containing the execution point is known to be a native method.
- Overrides:
toString in class Object
- Returns:
- a string representation of the object.
- See Also:
Throwable.printStackTrace()
equals
public boolean equals(Object obj)
- Returns true if the specified object is another
StackTraceElement instance representing the same execution
point as this instance. Two stack trace elements a and
b are equal if and only if:
equals(a.getFileName(), b.getFileName()) &&
a.getLineNumber() == b.getLineNumber()) &&
equals(a.getClassName(), b.getClassName()) &&
equals(a.getMethodName(), b.getMethodName())
where equals is defined as:
static boolean equals(Object a, Object b) {
return a==b || (a != null && a.equals(b));
}
- Overrides:
equals in class Object
- Parameters:
obj - the object to be compared with this stack trace element.
- Returns:
- true if the specified object is another
StackTraceElement instance representing the same
execution point as this instance.
- See Also:
Object.hashCode() ,
Hashtable
hashCode
public int hashCode()
- Returns a hash code value for this stack trace element.
- Overrides:
hashCode in class Object
- Returns:
- a hash code value for this object.
- See Also:
Object.equals(java.lang.Object) ,
Hashtable
Copyright 2003 Sun Microsystems, Inc. All rights reserved
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