Package org.apache.tapestry5.plastic

## Interface TryCatchBlock

- All Known Implementing Classes:
    `TryCatchBlockImpl`

      public interface TryCatchBlock

  Allows a portion of a method to be marked so that exception and finally handlers can be provided.
  See Also:
    `InstructionBuilder.startTryCatch(TryCatchCallback)`

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `void` | `addCatch​(java.lang.String exceptionClassName, InstructionBuilderCallback callback)` | Ends the block (if not already ended) and inserts a catch block for the named exception.
    `void` | `addFinally​(InstructionBuilderCallback callback)` | As with `addCatch(String, InstructionBuilderCallback)`, but the exception caught is null, which acts as a finally block in the Java language.
    `void` | `addTry​(InstructionBuilderCallback callback)` | Invoked first, to generate the code in which exceptions may be caught.

- - ### Method Detail

    - #### addTry

          void addTry​(InstructionBuilderCallback callback)

      Invoked first, to generate the code in which exceptions may be caught.

    - #### addCatch

          @Opcodes("TRYCATCHBLOCK")
          void addCatch​(java.lang.String exceptionClassName,
                        InstructionBuilderCallback callback)

      Ends the block (if not already ended) and inserts a catch block for the named exception. The InstructionBuilder is returned so that the code for handling the exception can be added. The exception object will be on top of the stack. This should be called after `addTry(InstructionBuilderCallback)`. Note: no attempt is made currently to sort the handlers; for example adding a catch for java.lang.Exception first will mean that more specific exception handlers added later will never be invoked.
      Parameters:
        `exceptionClassName` - caught exception class
        `callback` - that implements the logic of the catch block

    - #### addFinally

          @Opcodes("TRYCATCHBLOCK")
          void addFinally​(InstructionBuilderCallback callback)

      As with `addCatch(String, InstructionBuilderCallback)`, but the exception caught is null, which acts as a finally block in the Java language. This must be called last (after `addTry(InstructionBuilderCallback)` and any calls to `addCatch(String, InstructionBuilderCallback)`.
      Parameters:
        `callback` - implements the logic of the finally block