Class java.lang.Throwable - JDK 5 Documentation v1.1.8, Java 2 SDK 英文文档

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Class java.lang.Throwable

java.lang.Object
   |
   +----java.lang.Throwable

public class Throwable
extends Object
implements Serializable

The Throwable class is the superclass of all errors and exceptions in the Java language. Only objects that are instances of this class (or of one of its subclasses) are thrown by the Java Virtual Machine or can be thrown by the Java throw statement. Similarly, only this class or one of its subclasses can be the argument type in a catch clause.

A Throwable class contains a snapshot of the execution stack of its thread at the time it was created. It can also contain a message string that gives more information about the error.

Here is one example of catching an exception:

     try {
         int a[] = new int[2];
         a[4];
     } catch (ArrayIndexOutOfBoundsException e) {
         System.out.println("exception: " + e.getMessage());
         e.printStackTrace();
     }

Throwable(): Constructs a new Throwable with no detail message.
Throwable(String): Constructs a new Throwable with the specified detail message.

fillInStackTrace(): Fills in the execution stack trace.
getLocalizedMessage(): Creates a localized description of this Throwable.
getMessage(): Returns the detail message of this throwable object.
printStackTrace(): Prints this Throwable and its backtrace to the standard error stream.
printStackTrace(PrintStream): Prints this Throwable and its backtrace to the specified print stream.
printStackTrace(PrintWriter): Prints this Throwable and its backtrace to the specified print writer.
toString(): Returns a short description of this throwable object.

Throwable

 public Throwable()

Constructs a new Throwable with no detail message. The stack trace is automatically filled in.

Throwable

 public Throwable(String message)

Constructs a new Throwable with the specified detail message. The stack trace is automatically filled in.

Parameters:: message - the detail message.

getMessage

 public String getMessage()

Returns the detail message of this throwable object.

Returns:: the detail message of this Throwable, or null if this Throwable does not have a detail message.

getLocalizedMessage

 public String getLocalizedMessage()

Creates a localized description of this Throwable. Subclasses may override this method in order to produce a locale-specific message. For subclasses that do not override this method, the default implementation returns the same result as getMessage().

toString

 public String toString()

Returns a short description of this throwable object.

Returns:: a string representation of this Throwable.
Overrides:: toString in class Object

printStackTrace

 public void printStackTrace()

Prints this Throwable and its backtrace to the standard error stream.

See Also:: err

printStackTrace

 public void printStackTrace(PrintStream s)

Prints this Throwable and its backtrace to the specified print stream.

printStackTrace

 public void printStackTrace(PrintWriter s)

Prints this Throwable and its backtrace to the specified print writer.

fillInStackTrace

 public native Throwable fillInStackTrace()

Fills in the execution stack trace. This method is useful when an application is re-throwing an error or exception. For example:

     try {
         a = b / c;
     } catch(ArithmeticThrowable e) {
         a = Number.MAX_VALUE;
         throw e.fillInStackTrace();
     }

Returns:: this Throwable object.
See Also:: printStackTrace

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