Java compact1, compact2, compact3 java.lang Class StackTraceElement（JDK8）

Constructor Detail

• 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 element

  methodName - the name of the method containing the execution point represented by the stack trace element

  fileName - the name of the file containing the execution point represented by the stack trace element, or null if this information is unavailable

  lineNumber - 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

Method Detail

• 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 has the semantics of Objects.equals.

  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(), HashMap

• 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), System.identityHashCode(java.lang.Object)