TwillPreparer (Apache Twill API 0.8.0 API)

```
public interface TwillPreparer
```
This interface exposes methods to set up the Twill runtime environment and start a Twill application.

Method Summary

Methods
Modifier and Type	Method and Description
`TwillPreparer`	`addJVMOptions(String options)` This methods adds extra JVM options that will be passed to the java command line for every runnable of the application started through this `TwillPreparer` instance.
`TwillPreparer`	`addLogHandler(LogHandler handler)` Adds a `LogHandler` for receiving an application log.
`TwillPreparer`	`addSecureStore(SecureStore secureStore)` Adds security credentials for the runtime environment to gives application access to resources.
`TwillPreparer`	`enableDebugging(boolean doSuspend, String... runnables)` Enable debugging for runnables.
`TwillPreparer`	`enableDebugging(String... runnables)` Enable debugging for runnables, without suspending the virtual machine to wait for the debugger.
`TwillPreparer`	`setJVMOptions(String options)` This methods sets the extra JVM options that will be passed to the java command line for every runnable of the application started through this `TwillPreparer` instance.
`TwillPreparer`	`setLogLevel(LogEntry.Level logLevel)` Set the log level for Twill applications running in a container.
`TwillPreparer`	`setSchedulerQueue(String name)` Sets the name of the scheduler queue to use.
`TwillPreparer`	`setUser(String user)` Deprecated. This method will be removed in future version.
`TwillController`	`start()` Starts the application.
`TwillPreparer`	`withApplicationArguments(Iterable<String> args)` Sets the list of arguments that will be passed to the application.
`TwillPreparer`	`withApplicationArguments(String... args)` Sets the list of arguments that will be passed to the application.
`TwillPreparer`	`withApplicationClassPaths(Iterable<String> classPaths)` Adds the set of paths to the classpath on the target machine for ApplicationMaster and all runnables.
`TwillPreparer`	`withApplicationClassPaths(String... classPaths)` Adds the set of paths to the classpath on the target machine for ApplicationMaster and all runnables.
`TwillPreparer`	`withArguments(String runnableName, Iterable<String> args)` Sets the list of arguments that will be passed to the `TwillRunnable` identified by the given name.
`TwillPreparer`	`withArguments(String runnableName, String... args)` Sets the list of arguments that will be passed to the `TwillRunnable` identified by the given name.
`TwillPreparer`	`withBundlerClassAcceptor(ClassAcceptor classAcceptor)` Uses `ClassAcceptor` to determine the classes to include in the bundle jar for ApplicationMaster and all runnables.
`TwillPreparer`	`withClassPaths(Iterable<String> classPaths)` Adds the set of paths to the classpath on the target machine for all runnables.
`TwillPreparer`	`withClassPaths(String... classPaths)` Adds the set of paths to the classpath on the target machine for all runnables.
`TwillPreparer`	`withDependencies(Class<?>... classes)` Adds extra classes that the application is dependent on and is not traceable from the application itself.
`TwillPreparer`	`withDependencies(Iterable<Class<?>> classes)` Adds extra classes that the application is dependent on and is not traceable from the application itself.
`TwillPreparer`	`withEnv(Map<String,String> env)` Adds the set of environment variables that will be set as container environment variables for all runnables.
`TwillPreparer`	`withEnv(String runnableName, Map<String,String> env)` Adds the set of environment variables that will be set as container environment variables for the given runnable.
`TwillPreparer`	`withResources(Iterable<URI> resources)` Adds resources that will be available through the ClassLoader of the `runnables`.
`TwillPreparer`	`withResources(URI... resources)` Adds resources that will be available through the ClassLoader of the `runnables`.

- Method Detail
  - addLogHandler
```
TwillPreparer addLogHandler(LogHandler handler)
```
    Adds a LogHandler for receiving an application log.
    
    Parameters:
    handler - The LogHandler.
    
    Returns:
    This TwillPreparer.
  - setUser
```
@Deprecated
TwillPreparer setUser(String user)
```
    Deprecated. This method will be removed in future version.
    
    Sets the user name that runs the application. Default value is get from "user.name" by calling System.getProperty(String).
    
    Parameters:
    user - User name
    
    Returns:
    This TwillPreparer.
  - setSchedulerQueue
```
TwillPreparer setSchedulerQueue(String name)
```
    Sets the name of the scheduler queue to use.
    
    Parameters:
    name - Name of the scheduler queue
    
    Returns:
    This TwillPreparer.
  - setJVMOptions
```
TwillPreparer setJVMOptions(String options)
```
    This methods sets the extra JVM options that will be passed to the java command line for every runnable of the application started through this TwillPreparer instance. This is intended for advance usage. All options will be passed unchanged to the java command line. Invalid options could cause application not able to start.
    
    Parameters:
    options - extra JVM options.
  - addJVMOptions
```
TwillPreparer addJVMOptions(String options)
```
    This methods adds extra JVM options that will be passed to the java command line for every runnable of the application started through this TwillPreparer instance. This is intended for advance usage. All options will be passed unchanged to the java command line. Invalid options could cause application not able to start.
    
    Parameters:
    options - extra JVM options.
  - enableDebugging
```
TwillPreparer enableDebugging(String... runnables)
```
    Enable debugging for runnables, without suspending the virtual machine to wait for the debugger. This replaces any previous debug settings.
    
    Parameters:
    runnables - the names of runnables to enable for debugging. If empty, it means all runnables.
  - enableDebugging
```
TwillPreparer enableDebugging(boolean doSuspend,
                            String... runnables)
```
    Enable debugging for runnables. This replaces any previous debug settings.
    
    Parameters:
    doSuspend - whether the virtual machines should be supended until the debugger connects. This option allows to debug a container from the very beginning. Note that in that case, the container cannot notify the controller of its debug port until the debugger is attached - you must figure out where it is running using the YARN console or APIs.
    runnables - the names of runnables to enable for debugging. If empty, it means all runnables.
  - withApplicationArguments
```
TwillPreparer withApplicationArguments(String... args)
```
    Sets the list of arguments that will be passed to the application. The arguments can be retrieved from TwillContext.getApplicationArguments().
    
    Parameters:
    args - Array of arguments.
    
    Returns:
    This TwillPreparer.
  - withApplicationArguments
```
TwillPreparer withApplicationArguments(Iterable<String> args)
```
    Sets the list of arguments that will be passed to the application. The arguments can be retrieved from TwillContext.getApplicationArguments().
    
    Parameters:
    args - Iterable of arguments.
    
    Returns:
    This TwillPreparer.
  - withArguments
```
TwillPreparer withArguments(String runnableName,
                          String... args)
```
    Sets the list of arguments that will be passed to the TwillRunnable identified by the given name. The arguments can be retrieved from TwillContext.getArguments().
    
    Parameters:
    runnableName - Name of the TwillRunnable.
    args - Array of arguments.
    
    Returns:
    This TwillPreparer.
  - withArguments
```
TwillPreparer withArguments(String runnableName,
                          Iterable<String> args)
```
    Sets the list of arguments that will be passed to the TwillRunnable identified by the given name. The arguments can be retrieved from TwillContext.getArguments().
    
    Parameters:
    runnableName - Name of the TwillRunnable.
    args - Iterable of arguments.
    
    Returns:
    This TwillPreparer.
  - withDependencies
```
TwillPreparer withDependencies(Class<?>... classes)
```
    Adds extra classes that the application is dependent on and is not traceable from the application itself.
    
    Returns:
    This TwillPreparer.
    See Also:
    withDependencies(Iterable)
  - withDependencies
```
TwillPreparer withDependencies(Iterable<Class<?>> classes)
```
    Adds extra classes that the application is dependent on and is not traceable from the application itself. E.g. Class name used in Class.forName(String).
    
    Parameters:
    classes - set of classes to add to dependency list for generating the deployment jar.
    
    Returns:
    This TwillPreparer.
  - withResources
```
TwillPreparer withResources(URI... resources)
```
    Adds resources that will be available through the ClassLoader of the runnables.
    
    Returns:
    This TwillPreparer.
    See Also:
    withResources(Iterable)
  - withResources
```
TwillPreparer withResources(Iterable<URI> resources)
```
    Adds resources that will be available through the ClassLoader of the runnables. Useful for adding extra resource files or libraries that are not traceable from the application itself. If the URI is a jar file, classes inside would be loadable by the ClassLoader. If the URI is a directory, everything underneath would be available.
    
    Parameters:
    resources - Set of URI to the resources.
    
    Returns:
    This TwillPreparer.
  - withClassPaths
```
TwillPreparer withClassPaths(String... classPaths)
```
    Adds the set of paths to the classpath on the target machine for all runnables.
    
    Returns:
    This TwillPreparer
    See Also:
    withClassPaths(Iterable)
  - withClassPaths
```
TwillPreparer withClassPaths(Iterable<String> classPaths)
```
    Adds the set of paths to the classpath on the target machine for all runnables. Note that the paths would be just added without verification.
    
    Parameters:
    classPaths - Set of classpaths
    
    Returns:
    This TwillPreparer
  - withEnv
```
TwillPreparer withEnv(Map<String,String> env)
```
    Adds the set of environment variables that will be set as container environment variables for all runnables.
    
    Parameters:
    env - set of environment variables
    
    Returns:
    This TwillPreparer
  - withEnv
```
TwillPreparer withEnv(String runnableName,
                    Map<String,String> env)
```
    Adds the set of environment variables that will be set as container environment variables for the given runnable. Environment variables set through this method has higher precedence than the one set through withEnv(Map) if there is a key clash.
    
    Parameters:
    runnableName - Name of the TwillRunnable.
    env - set of environment variables
    
    Returns:
    This TwillPreparer
  - withApplicationClassPaths
```
TwillPreparer withApplicationClassPaths(String... classPaths)
```
    Adds the set of paths to the classpath on the target machine for ApplicationMaster and all runnables.
    
    Returns:
    This TwillPreparer
  - withApplicationClassPaths
```
TwillPreparer withApplicationClassPaths(Iterable<String> classPaths)
```
    Adds the set of paths to the classpath on the target machine for ApplicationMaster and all runnables.
    
    Returns:
    This TwillPreparer
  - withBundlerClassAcceptor
```
TwillPreparer withBundlerClassAcceptor(ClassAcceptor classAcceptor)
```
    Uses ClassAcceptor to determine the classes to include in the bundle jar for ApplicationMaster and all runnables.
    
    Parameters:
    classAcceptor - to specify which classes to include in the bundle jar
    
    Returns:
    This TwillPreparer
  - addSecureStore
```
TwillPreparer addSecureStore(SecureStore secureStore)
```
    Adds security credentials for the runtime environment to gives application access to resources.
    
    Parameters:
    secureStore - Contains security token available for the runtime environment.
    
    Returns:
    This TwillPreparer.
  - setLogLevel
```
TwillPreparer setLogLevel(LogEntry.Level logLevel)
```
    Set the log level for Twill applications running in a container.
    
    Parameters:
    logLevel - the LogEntry.Level that should be set. The level match the Logback levels.
    
    Returns:
    This TwillPreparer.
  - start
```
TwillController start()
```
    Starts the application.
    
    Returns:
    A TwillController for controlling the running application.

Interface TwillPreparer

Method Summary

Method Detail

addLogHandler

setUser

setSchedulerQueue

setJVMOptions

addJVMOptions

enableDebugging

enableDebugging

withApplicationArguments

withApplicationArguments

withArguments

withArguments

withDependencies

withDependencies

withResources

withResources

withClassPaths

withClassPaths

withEnv

withEnv

withApplicationClassPaths

withApplicationClassPaths

withBundlerClassAcceptor

addSecureStore

setLogLevel

start