Package org.apache.tools.ant.taskdefs

## Class Java

- java.lang.Object
- - org.apache.tools.ant.ProjectComponent
  - - org.apache.tools.ant.Task
    - - org.apache.tools.ant.taskdefs.Java

All Implemented Interfaces:
  `java.lang.Cloneable`

    public class Java
    extends Task

Launcher for Java applications. Allows use of the same JVM for the called application thus resulting in much faster operation.

Since:
  Ant 1.1

### Field Summary

Fields
`protected Redirector` `redirector`
`protected RedirectorElement` `redirectorElement`

### 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
`Java()` Normal constructor
`Java​(Task owner)` create a bound task

### Method Summary

All Methods Instance Methods Concrete Methods
`void` `addAssertions​(Assertions asserts)` Add assertions to enable in this program (if fork=true).
`void` `addConfiguredRedirector​(RedirectorElement redirectorElement)` Add a `RedirectorElement` to this task.
`void` `addEnv​(Environment.Variable var)` Add an environment variable.
`void` `addSysproperty​(Environment.Variable sysp)` Add a system property.
`void` `addSyspropertyset​(PropertySet sysp)` Add a set of properties as system properties.
`protected void` `checkConfiguration()` Check configuration.
`void` `clearArgs()` Clear out the arguments to this java task.
`Commandline.Argument` `createArg()` Add a command-line argument.
`Path` `createBootclasspath()` Add a path to the bootclasspath.
`Path` `createClasspath()` Add a path to the classpath.
`Commandline.Argument` `createJvmarg()` Adds a JVM argument.
`Path` `createModulepath()` Add a path to the modulepath.
`Permissions` `createPermissions()` Set the permissions for the application run inside the same JVM.
`Path` `createUpgrademodulepath()` Add a path to the upgrademodulepath.
`protected ExecuteWatchdog` `createWatchdog()` Create the Watchdog to kill a runaway process.
`void` `execute()` Do the execution.
`int` `executeJava()` Do the execution and return a return code.
`protected int` `executeJava​(CommandlineJava commandLine)` Execute the specified CommandlineJava.
`CommandlineJava` `getCommandLine()` Accessor to the command line.
`CommandlineJava.SysProperties` `getSysProperties()` Get the system properties of the command line.
`protected void` `handleErrorFlush​(java.lang.String output)` Handle output sent to System.err and flush the stream.
`protected void` `handleErrorOutput​(java.lang.String output)` Handle output sent to System.err.
`protected void` `handleFlush​(java.lang.String output)` Pass output sent to System.out to specified output file.
`int` `handleInput​(byte[] buffer, int offset, int length)` Handle an input request by this task.
`protected void` `handleOutput​(java.lang.String output)` Pass output sent to System.out to specified output file.
`protected void` `maybeSetResultPropertyValue​(int result)` Helper method to set result property to the passed in value if appropriate.
`protected void` `run​(java.lang.String classname, java.util.Vector<java.lang.String> args)` Executes the given classname with the given arguments as if it were a command line application.
`void` `setAppend​(boolean append)` If true, append output to existing file.
`void` `setArgs​(java.lang.String s)` Deprecated: use nested arg instead.
`void` `setClassname​(java.lang.String s)` Set the Java class to execute.
`void` `setClasspath​(Path s)` Set the classpath to be used when running the Java class.
`void` `setClasspathRef​(Reference r)` Set the classpath to use by reference.
`void` `setCloneVm​(boolean cloneVm)` If set, system properties will be copied to the cloned VM--as well as the bootclasspath unless you have explicitly specified a bootclasspath.
`void` `setDir​(java.io.File d)` Set the working directory of the process.
`void` `setDiscardError​(boolean discard)` Whether error output should be discarded.
`void` `setDiscardOutput​(boolean discard)` Whether output should be discarded.
`void` `setError​(java.io.File error)` Set the File to which the error stream of the process is redirected.
`void` `setErrorProperty​(java.lang.String errorProperty)` Set the property name whose value should be set to the error of the process.
`void` `setFailonerror​(boolean fail)` If true, then fail if the command exits with a returncode other than zero.
`void` `setFork​(boolean s)` If true, execute in a new VM.
`void` `setInput​(java.io.File input)` Set the input to use for the task.
`void` `setInputString​(java.lang.String inputString)` Set the string to use as input.
`void` `setJar​(java.io.File jarfile)` Set the location of the JAR file to execute.
`void` `setJvm​(java.lang.String s)` Set the command used to start the VM (only if forking).
`void` `setJvmargs​(java.lang.String s)` Set the command line arguments for the JVM.
`void` `setJVMVersion​(java.lang.String value)` Set the JVM version.
`void` `setLogError​(boolean logError)` Set whether error output of exec is logged.
`void` `setMaxmemory​(java.lang.String max)` Corresponds to -mx or -Xmx depending on VM version.
`void` `setModule​(java.lang.String module)` Set the Java module to execute.
`void` `setModulepath​(Path mp)` Set the modulepath to be used when running the Java class.
`void` `setModulepathRef​(Reference r)` Set the modulepath to use by reference.
`void` `setNewenvironment​(boolean newenv)` If true, use a completely new environment.
`void` `setOutput​(java.io.File out)` Set the File to which the output of the process is redirected.
`void` `setOutputproperty​(java.lang.String outputProp)` Set the property name whose value should be set to the output of the process.
`void` `setResultProperty​(java.lang.String resultProperty)` Set the name of the property in which the return code of the command should be stored.
`void` `setSourceFile​(java.lang.String sourceFile)` Set the Java source-file to execute.
`void` `setSpawn​(boolean spawn)` Set whether or not you want the process to be spawned; default is not spawned.
`void` `setTimeout​(java.lang.Long value)` Set the timeout in milliseconds after which the process will be killed.
`protected void` `setupRedirector()` Set up properties on the redirector that we needed to store locally.

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

`bindToOwner, getOwningTarget, getRuntimeConfigurableWrapper, getTaskName, getTaskType, getWrapper, 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 java.lang.Object

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

### Field Detail

#### redirector

    protected Redirector redirector

#### redirectorElement

    protected RedirectorElement redirectorElement

### Constructor Detail

#### Java

    public Java()

Normal constructor

#### Java

    public Java​(Task owner)

create a bound task

Parameters:
  `owner` - owner

### Method Detail

#### execute

    public void execute()
                 throws BuildException

Do the execution.

Overrides:
  `execute` in class `Task`
Throws:
  `BuildException` - if failOnError is set to true and the application returns a nonzero result code.

#### executeJava

    public int executeJava()
                    throws BuildException

Do the execution and return a return code.

Returns:
  the return code from the execute java class if it was executed in a separate VM (fork = "yes") or a security manager was installed that prohibits ExitVM (default).
Throws:
  `BuildException` - if required parameters are missing.

#### checkConfiguration

    protected void checkConfiguration()
                               throws BuildException

Check configuration.

Throws:
  `BuildException` - if required parameters are missing.

#### executeJava

    protected int executeJava​(CommandlineJava commandLine)

Execute the specified CommandlineJava.

Parameters:
  `commandLine` - CommandLineJava instance.
Returns:
  the exit value of the process if forked, 0 otherwise.

#### setSpawn

    public void setSpawn​(boolean spawn)

Set whether or not you want the process to be spawned; default is not spawned.

Parameters:
  `spawn` - if true you do not want Ant to wait for the end of the process.
Since:
  Ant 1.6

#### setClasspath

    public void setClasspath​(Path s)

Set the classpath to be used when running the Java class.

Parameters:
  `s` - an Ant Path object containing the classpath.

#### createClasspath

    public Path createClasspath()

Add a path to the classpath.

Returns:
  created classpath.

#### createBootclasspath

    public Path createBootclasspath()

Add a path to the bootclasspath.

Returns:
  created bootclasspath.
Since:
  Ant 1.6

#### setModulepath

    public void setModulepath​(Path mp)

Set the modulepath to be used when running the Java class.

Parameters:
  `mp` - an Ant Path object containing the modulepath.
Since:
  1.9.7

#### createModulepath

    public Path createModulepath()

Add a path to the modulepath.

Returns:
  created modulepath.
Since:
  1.9.7

#### setModulepathRef

    public void setModulepathRef​(Reference r)

Set the modulepath to use by reference.

Parameters:
  `r` - a reference to an existing modulepath.
Since:
  1.9.7

#### createUpgrademodulepath

    public Path createUpgrademodulepath()

Add a path to the upgrademodulepath.

Returns:
  created upgrademodulepath.
Since:
  1.9.7

#### createPermissions

    public Permissions createPermissions()

Set the permissions for the application run inside the same JVM.

Returns:
  Permissions.
Since:
  Ant 1.6

#### setClasspathRef

    public void setClasspathRef​(Reference r)

Set the classpath to use by reference.

Parameters:
  `r` - a reference to an existing classpath.

#### setJar

    public void setJar​(java.io.File jarfile)
                throws BuildException

Set the location of the JAR file to execute.

Parameters:
  `jarfile` - the jarfile to execute.
Throws:
  `BuildException` - if there is also a `classname`, `module` or `sourcefile` attribute specified

#### setClassname

    public void setClassname​(java.lang.String s)
                      throws BuildException

Set the Java class to execute.

Parameters:
  `s` - the name of the main class.
Throws:
  `BuildException` - if there is also a `jar` or `sourcefile` attribute specified

#### setModule

    public void setModule​(java.lang.String module)
                   throws BuildException

Set the Java module to execute.

Parameters:
  `module` - the name of the module.
Throws:
  `BuildException` - if there is also a `jar` or `sourcefile` attribute specified
Since:
  1.9.7

#### setSourceFile

    public void setSourceFile​(java.lang.String sourceFile)
                       throws BuildException

Set the Java source-file to execute. Support for single file source program execution, in Java, is only available since Java 11.

Parameters:
  `sourceFile` - The path to the source file
Throws:
  `BuildException` - if there is also a `jar`, `classname` or `module` attribute specified
Since:
  Ant 1.10.5

#### setArgs

    public void setArgs​(java.lang.String s)

Deprecated: use nested arg instead. Set the command line arguments for the class.

Parameters:
  `s` - arguments.

#### setCloneVm

    public void setCloneVm​(boolean cloneVm)

If set, system properties will be copied to the cloned VM--as well as the bootclasspath unless you have explicitly specified a bootclasspath.

Doesn't have any effect unless fork is true.

Parameters:
  `cloneVm` - if true copy system properties.
Since:
  Ant 1.7

#### createArg

    public Commandline.Argument createArg()

Add a command-line argument.

Returns:
  created argument.

#### setResultProperty

    public void setResultProperty​(java.lang.String resultProperty)

Set the name of the property in which the return code of the command should be stored. Only of interest if failonerror=false.

Parameters:
  `resultProperty` - name of property.
Since:
  Ant 1.6

#### maybeSetResultPropertyValue

    protected void maybeSetResultPropertyValue​(int result)

Helper method to set result property to the passed in value if appropriate.

Parameters:
  `result` - the exit code

#### setFork

    public void setFork​(boolean s)

If true, execute in a new VM.

Parameters:
  `s` - do you want to run Java in a new VM.

#### setJvmargs

    public void setJvmargs​(java.lang.String s)

Set the command line arguments for the JVM.

Parameters:
  `s` - jvmargs.

#### createJvmarg

    public Commandline.Argument createJvmarg()

Adds a JVM argument.

Returns:
  JVM argument created.

#### setJvm

    public void setJvm​(java.lang.String s)

Set the command used to start the VM (only if forking).

Parameters:
  `s` - command to start the VM.

#### addSysproperty

    public void addSysproperty​(Environment.Variable sysp)

Add a system property.

Parameters:
  `sysp` - system property.

#### addSyspropertyset

    public void addSyspropertyset​(PropertySet sysp)

Add a set of properties as system properties.

Parameters:
  `sysp` - set of properties to add.
Since:
  Ant 1.6

#### setFailonerror

    public void setFailonerror​(boolean fail)

If true, then fail if the command exits with a returncode other than zero.

Parameters:
  `fail` - if true fail the build when the command exits with a nonzero returncode.

#### setDir

    public void setDir​(java.io.File d)

Set the working directory of the process.

Parameters:
  `d` - working directory.

#### setOutput

    public void setOutput​(java.io.File out)

Set the File to which the output of the process is redirected.

Parameters:
  `out` - the output File.

#### setInput

    public void setInput​(java.io.File input)

Set the input to use for the task.

Parameters:
  `input` - name of the input file.

#### setInputString

    public void setInputString​(java.lang.String inputString)

Set the string to use as input.

Parameters:
  `inputString` - the string which is used as the input source.

#### setLogError

    public void setLogError​(boolean logError)

Set whether error output of exec is logged. This is only useful when output is being redirected and error output is desired in the Ant log.

Parameters:
  `logError` - get in the ant log the messages coming from stderr in the case that fork = true.

#### setError

    public void setError​(java.io.File error)

Set the File to which the error stream of the process is redirected.

Parameters:
  `error` - file getting the error stream.
Since:
  Ant 1.6

#### setOutputproperty

    public void setOutputproperty​(java.lang.String outputProp)

Set the property name whose value should be set to the output of the process.

Parameters:
  `outputProp` - property name.

#### setErrorProperty

    public void setErrorProperty​(java.lang.String errorProperty)

Set the property name whose value should be set to the error of the process.

Parameters:
  `errorProperty` - property name.
Since:
  Ant 1.6

#### setMaxmemory

    public void setMaxmemory​(java.lang.String max)

Corresponds to -mx or -Xmx depending on VM version.

Parameters:
  `max` - max memory parameter.

#### setJVMVersion

    public void setJVMVersion​(java.lang.String value)

Set the JVM version.

Parameters:
  `value` - JVM version.

#### addEnv

    public void addEnv​(Environment.Variable var)

Add an environment variable.

Will be ignored if we are not forking a new VM.

Parameters:
  `var` - new environment variable.
Since:
  Ant 1.5

#### setNewenvironment

    public void setNewenvironment​(boolean newenv)

If true, use a completely new environment.

Will be ignored if we are not forking a new VM.

Parameters:
  `newenv` - if true, use a completely new environment.
Since:
  Ant 1.5

#### setAppend

    public void setAppend​(boolean append)

If true, append output to existing file.

Parameters:
  `append` - if true, append output to existing file.
Since:
  Ant 1.5

#### setDiscardOutput

    public void setDiscardOutput​(boolean discard)

Whether output should be discarded.

Defaults to false.

Parameters:
  `discard` - if true output streams are discarded.
Since:
  Ant 1.10.10
See Also:
  `setDiscardError(boolean)`

#### setDiscardError

    public void setDiscardError​(boolean discard)

Whether error output should be discarded.

Defaults to false.

Parameters:
  `discard` - if true error streams are discarded.
Since:
  Ant 1.10.10
See Also:
  `setDiscardOutput(boolean)`

#### setTimeout

    public void setTimeout​(java.lang.Long value)

Set the timeout in milliseconds after which the process will be killed.

Parameters:
  `value` - timeout in milliseconds.
Since:
  Ant 1.5

#### addAssertions

    public void addAssertions​(Assertions asserts)

Add assertions to enable in this program (if fork=true).

Parameters:
  `asserts` - assertion set.
Since:
  Ant 1.6

#### addConfiguredRedirector

    public void addConfiguredRedirector​(RedirectorElement redirectorElement)

Add a `RedirectorElement` to this task.

Parameters:
  `redirectorElement` - `RedirectorElement`.

#### handleOutput

    protected void handleOutput​(java.lang.String output)

Pass output sent to System.out to specified output file.

Overrides:
  `handleOutput` in class `Task`
Parameters:
  `output` - a string of output on its way to the handlers.
Since:
  Ant 1.5

#### handleInput

    public int handleInput​(byte[] buffer,
                           int offset,
                           int length)
                    throws java.io.IOException

Handle an input request by this task.

Overrides:
  `handleInput` in class `Task`
Parameters:
  `buffer` - the buffer into which data is to be read.
  `offset` - the offset into the buffer at which data is stored.
  `length` - the amount of data to read.
Returns:
  the number of bytes read.
Throws:
  `java.io.IOException` - if the data cannot be read.
Since:
  Ant 1.6

#### handleFlush

    protected void handleFlush​(java.lang.String output)

Pass output sent to System.out to specified output file.

Overrides:
  `handleFlush` in class `Task`
Parameters:
  `output` - string of output on its way to its handlers.
Since:
  Ant 1.5.2

#### handleErrorOutput

    protected void handleErrorOutput​(java.lang.String output)

Handle output sent to System.err.

Overrides:
  `handleErrorOutput` in class `Task`
Parameters:
  `output` - string of stderr.
Since:
  Ant 1.5

#### handleErrorFlush

    protected void handleErrorFlush​(java.lang.String output)

Handle output sent to System.err and flush the stream.

Overrides:
  `handleErrorFlush` in class `Task`
Parameters:
  `output` - string of stderr.
Since:
  Ant 1.5.2

#### setupRedirector

    protected void setupRedirector()

Set up properties on the redirector that we needed to store locally.

#### run

    protected void run​(java.lang.String classname,
                       java.util.Vector<java.lang.String> args)
                throws BuildException

Executes the given classname with the given arguments as if it were a command line application.

Parameters:
  `classname` - the name of the class to run.
  `args` - arguments for the class.
Throws:
  `BuildException` - in case of IOException in the execution.

#### clearArgs

    public void clearArgs()

Clear out the arguments to this java task.

#### createWatchdog

    protected ExecuteWatchdog createWatchdog()
                                      throws BuildException

Create the Watchdog to kill a runaway process.

Returns:
  new watchdog.
Throws:
  `BuildException` - under unknown circumstances.
Since:
  Ant 1.5

#### getCommandLine

    public CommandlineJava getCommandLine()

Accessor to the command line.

Returns:
  the current command line.
Since:
  1.6.3

#### getSysProperties

    public CommandlineJava.SysProperties getSysProperties()

Get the system properties of the command line.

Returns:
  the current properties of this java invocation.
Since:
  1.6.3