org.springframework.data.hadoop.scripting

Class HdfsScriptRunner

java.lang.Object

org.springframework.data.hadoop.scripting.HdfsScriptRunner

All Implemented Interfaces:

java.util.concurrent.Callable<java.lang.Object>, org.springframework.beans.factory.Aware, org.springframework.beans.factory.BeanClassLoaderAware, org.springframework.beans.factory.InitializingBean, org.springframework.context.ApplicationContextAware

public class HdfsScriptRunner
extends java.lang.Object
implements org.springframework.context.ApplicationContextAware

Hadoop-customized runner that exposes Hadoop specific variables to scripting languages. The instances exposes are reused from the enclosing context (using naming conventions or autowiring strategies) or created on demand (in case of lightweight objects).

These are :

variables

Name	Type	Description
cfg	org.apache.hadoop.conf.Configuration	Hadoop Configuration (relies on 'hadoop-configuration' bean or singleton type match)
cl	java.lang.ClassLoader	ClassLoader used for executing this script
ctx	org.springframework.context.ApplicationContext	Enclosing application context
ctxRL	org.springframework.io.support.ResourcePatternResolver	Enclosing application context ResourceLoader (same as ctx)
distcp	org.springframework.data.hadoop.fs.DistributedCopyUtil	programmatic access to DistCp
fs	org.apache.hadoop.fs.FileSystem	Hadoop File System (relies on 'hadoop-fs' bean or singleton type match, falls back to creating one based on 'cfg')
fsh	org.springframework.data.hadoop.fs.FsShell	File System shell, exposing hadoop 'fs' commands as an API
hdfsRL	org.springframework.data.hadoop.io.HdfsResourceLoader	HdfsResourceLoader (relies on 'hadoop-resource-loader' or singleton type match, falls back to creating one automatically based on 'cfg')

Note that the above variables are added only if found (have a non-null value) and the keys are not bound already. To make the runner execute at startup, use setRunAtStartup(boolean).

Author:

Costin Leau

See Also:

HdfsResourceLoader, FsShell, ApplicationContext

Constructor Summary

Constructors

Constructor and Description
HdfsScriptRunner()

Method Summary

Methods

Modifier and Type	Method and Description
void	afterPropertiesSet()
java.lang.Object	call()
boolean	isRunAtStartup() Indicates whether the script gets executed once the factory bean initializes.
protected void	postProcess(java.util.Map<java.lang.String,java.lang.Object> args) Method for post-processing arguments.
void	setApplicationContext(org.springframework.context.ApplicationContext applicationContext)
void	setArguments(java.util.Map<java.lang.String,java.lang.Object> arguments) Sets the arguments for evaluating this script.
void	setBeanClassLoader(java.lang.ClassLoader classLoader)
void	setConfiguration(org.apache.hadoop.conf.Configuration configuration) Sets the Hadoop configuration to use.
void	setEvaluate(EvaluationPolicy evaluation) Sets the way the script is evaluated.
void	setExtension(java.lang.String extension) Sets the script extension.
void	setLanguage(java.lang.String language) Sets the script language.
void	setPostAction(java.util.Collection<java.util.concurrent.Callable<?>> actions) Actions to be invoked after running the action.
void	setPreAction(java.util.Collection<java.util.concurrent.Callable<?>> actions) Actions to be invoked before running the action.
void	setRunAtStartup(boolean runAtStartup) Indicates whether to evaluate the script at startup (default) or not.
void	setScriptSource(org.springframework.scripting.ScriptSource script) Sets the script source to evaluate.

Methods inherited from class java.lang.Object

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

Constructor Detail

HdfsScriptRunner

public HdfsScriptRunner()

Method Detail

postProcess

protected void postProcess(java.util.Map<java.lang.String,java.lang.Object> args)

Method for post-processing arguments. Useful for enhancing (adding) new arguments to scripts being executed.

Parameters:

args - The arguments.

afterPropertiesSet

public void afterPropertiesSet()
                        throws java.lang.Exception

Specified by:

afterPropertiesSet in interface org.springframework.beans.factory.InitializingBean

Throws:

java.lang.Exception

setApplicationContext

public void setApplicationContext(org.springframework.context.ApplicationContext applicationContext)
                           throws org.springframework.beans.BeansException

Specified by:

setApplicationContext in interface org.springframework.context.ApplicationContextAware

Throws:

org.springframework.beans.BeansException

setConfiguration

public void setConfiguration(org.apache.hadoop.conf.Configuration configuration)

Sets the Hadoop configuration to use.

Parameters:

configuration - The configuration to set.

call

public java.lang.Object call()
                      throws java.lang.Exception

Specified by:

call in interface java.util.concurrent.Callable<java.lang.Object>

Throws:

java.lang.Exception

setBeanClassLoader

public void setBeanClassLoader(java.lang.ClassLoader classLoader)

Specified by:

setBeanClassLoader in interface org.springframework.beans.factory.BeanClassLoaderAware

setScriptSource

public void setScriptSource(org.springframework.scripting.ScriptSource script)

Sets the script source to evaluate.

Parameters:

script - The script to evaluate.

setLanguage

public void setLanguage(java.lang.String language)

Sets the script language.

Parameters:

language - The script language.

setExtension

public void setExtension(java.lang.String extension)

Sets the script extension. Used for detecting the language.

Parameters:

extension - The extension to set.

setEvaluate

public void setEvaluate(EvaluationPolicy evaluation)

Sets the way the script is evaluated.

Parameters:

evaluation - The evaluation.

setArguments

public void setArguments(java.util.Map<java.lang.String,java.lang.Object> arguments)

Sets the arguments for evaluating this script.

Parameters:

arguments - The arguments to set.

isRunAtStartup

public boolean isRunAtStartup()

Indicates whether the script gets executed once the factory bean initializes.

Returns:

true if the script runs or not during startup

setRunAtStartup

public void setRunAtStartup(boolean runAtStartup)

Indicates whether to evaluate the script at startup (default) or not.

Parameters:

runAtStartup - The runStartUp to set.

setPreAction

public void setPreAction(java.util.Collection<java.util.concurrent.Callable<?>> actions)

Actions to be invoked before running the action.

Parameters:

actions - The actions.

setPostAction

public void setPostAction(java.util.Collection<java.util.concurrent.Callable<?>> actions)

Actions to be invoked after running the action.

Parameters:

actions - The actions.