Class TryCatchTask

java.lang.Object
org.apache.tools.ant.ProjectComponent
org.apache.tools.ant.Task
net.sf.antcontrib.logic.TryCatchTask
All Implemented Interfaces:
Cloneable
public class TryCatchTask extends org.apache.tools.ant.Task
A wrapper that lets you run a set of tasks and optionally run a different set of tasks if the first set fails and yet another set after the first one has finished.

This mirrors Java's try/catch/finally.

The tasks inside of the required <try> element will be run. If one of them should throw a BuildException several things can happen:

  • If there is no <catch> block, the exception will be passed through to Ant.
  • If the property attribute has been set, a property of the given name will be set to the message of the exception.
  • If the reference attribute has been set, a reference of the given id will be created and point to the exception object.
  • If there is a <catch> block, the tasks nested into it will be run.

If a <finally> block is present, the task nested into it will be run, no matter whether the first tasks have thrown an exception or not.

Attributes:

Name Description Required
property Name of a property that will receive the message of the exception that has been caught (if any) No
reference Id of a reference that will point to the exception object that has been caught (if any) No

Use the following task to define the <trycatch> task before you use it the first time:

  <taskdef name="trycatch" 
           classname="net.sf.antcontrib.logic.TryCatchTask" />

Crude Example

<trycatch property="foo" reference="bar">
  <try>
    <fail>Tada!</fail>
  </try>

  <catch>
    <echo>In &lt;catch&gt;.</echo>
  </catch>

  <finally>
    <echo>In &lt;finally&gt;.</echo>
  </finally>
</trycatch>

<echo>As property: ${foo}</echo>
<property name="baz" refid="bar" />
<echo>From reference: ${baz}</echo>

results in

  [trycatch] Caught exception: Tada!
      [echo] In <catch>.
      [echo] In <finally>.
      [echo] As property: Tada!
      [echo] From reference: Tada!
Author:
Stefan Bodewig, Dan Ritchey

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static final class 
    TryCatchTask.CatchBlock
     

  • Field Summary

    Fields inherited from class org.apache.tools.ant.Task

    target, taskName, taskType, wrapper

    Fields inherited from class org.apache.tools.ant.ProjectComponent

    description, location, project

  • Constructor Summary

    Constructors
    Constructor
    Description
    TryCatchTask()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    addCatch(TryCatchTask.CatchBlock cb)
     
    void
    addFinally(org.apache.tools.ant.taskdefs.Sequential seq)
    Adds a nested <finally> block - at most one is allowed.
    void
    addTry(org.apache.tools.ant.taskdefs.Sequential seq)
    Adds a nested <try> block - one is required, more is forbidden.
    void
    execute()
    The heart of the task.
    void
    setProperty(String p)
    Sets the property attribute.
    void
    setReference(String r)
    Sets the reference attribute.

    Methods inherited from class org.apache.tools.ant.Task

    bindToOwner, getOwningTarget, getRuntimeConfigurableWrapper, getTaskName, getTaskType, getWrapper, handleErrorFlush, handleErrorOutput, handleFlush, handleInput, handleOutput, init, isInvalid, log, log, log, log, maybeConfigure, perform, reconfigure, setOwningTarget, setRuntimeConfigurableWrapper, setTaskName, setTaskType

    Methods inherited from class org.apache.tools.ant.ProjectComponent

    clone, getDescription, getLocation, getProject, setDescription, setLocation, setProject

    Methods inherited from class Object

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

  • Constructor Details

    • TryCatchTask

      public TryCatchTask()

  • Method Details

    • addTry

      public void addTry(org.apache.tools.ant.taskdefs.Sequential seq) throws org.apache.tools.ant.BuildException
      Adds a nested <try> block - one is required, more is forbidden.
      Throws:
      org.apache.tools.ant.BuildException

    • addCatch

      public void addCatch(TryCatchTask.CatchBlock cb)

    • addFinally

      public void addFinally(org.apache.tools.ant.taskdefs.Sequential seq) throws org.apache.tools.ant.BuildException
      Adds a nested <finally> block - at most one is allowed.
      Throws:
      org.apache.tools.ant.BuildException

    • setProperty

      public void setProperty(String p)
      Sets the property attribute.

    • setReference

      public void setReference(String r)
      Sets the reference attribute.

    • execute

      public void execute() throws org.apache.tools.ant.BuildException
      The heart of the task.
      Overrides:
      execute in class org.apache.tools.ant.Task
      Throws:
      org.apache.tools.ant.BuildException