org.apache.tools.ant
Class TaskConfigurationChecker

java.lang.Object
  extended by org.apache.tools.ant.TaskConfigurationChecker

public class TaskConfigurationChecker
extends java.lang.Object

Helper class for the check of the configuration of a given task. This class provides methods for making assumptions about the task configuration. After collecting all violations with assert* and fail methods the checkErrors will throw a BuildException with all collected messages or does nothing if there wasn't any error.

Example:

     public class MyTask extends Task {
         ...
         public void execute() {
             TaskConfigurationChecker checker = TaskConfigurationChecker(this);
             checker.assertConfig(
                 srcdir != null,
                 "Attribute 'srcdir' must be set.
             );
             checker.assertConfig(
                 srcdir.exists(),
                 "Srcdir (" + srcdir + ") must exist."
             );
             if (someComplexCondition()) {
                 fail("Complex condition failed.");
             }
             checker.checkErrors();
         }
     }
 

See Also:
Notification Pattern

Constructor Summary
TaskConfigurationChecker(Task task)
          Constructor.
 
Method Summary
 void assertConfig(boolean condition, java.lang.String errormessage)
          Asserts that a condition is true.
 void checkErrors()
          Checks if there are any collected errors and throws a BuildException with all messages if there was one or more.
 void fail(java.lang.String errormessage)
          Registers an error.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

TaskConfigurationChecker

public TaskConfigurationChecker(Task task)
Constructor.

Parameters:
task - which task should be checked
Method Detail

assertConfig

public void assertConfig(boolean condition,
                         java.lang.String errormessage)
Asserts that a condition is true.

Parameters:
condition - which condition to check
errormessage - errormessage to throw if a condition failed

fail

public void fail(java.lang.String errormessage)
Registers an error.

Parameters:
errormessage - the message for the registered error

checkErrors

public void checkErrors()
                 throws BuildException
Checks if there are any collected errors and throws a BuildException with all messages if there was one or more.

Throws:
BuildException - if one or more errors were registered