java.lang.Object
- org.apache.sysds.api.mlcontext.ScriptExecutor

```
public class ScriptExecutor
extends Object
```
ScriptExecutor executes a DML or PYDML Script object using SystemDS. This is accomplished by calling the execute(org.apache.sysds.api.mlcontext.Script) method.
Script execution via the MLContext API typically consists of the following steps:
1. Language Steps
  1. Parse script into program
  2. Live variable analysis
  3. Validate program
2. HOP (High-Level Operator) Steps
  1. Construct HOP DAGs
  2. Static rewrites
  3. Intra-/Inter-procedural analysis
  4. Dynamic rewrites
  5. Compute memory estimates
  6. Rewrite persistent reads and writes (MLContext-specific)
3. LOP (Low-Level Operator) Steps
  1. Contruct LOP DAGs
  2. Generate runtime program
  3. Execute runtime program
  4. Dynamic recompilation
Modifications to these steps can be accomplished by subclassing ScriptExecutor. For more information, please see the execute(org.apache.sysds.api.mlcontext.Script) method.

Constructor Summary

Constructors
Constructor	Description
`ScriptExecutor()`	ScriptExecutor constructor.
`ScriptExecutor(DMLConfig config)`	ScriptExecutor constructor, where the configuration properties are passed in.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`compile(Script script)`
`void`	`compile(Script script, boolean performHOPRewrites)`	Compile a DML or PYDML script.
`MLResults`	`execute(Script script)`	Execute a DML or PYDML script.
`DMLConfig`	`getConfig()`	Obtain the SystemDS configuration properties.
`DMLProgram`	`getDmlProgram()`	Obtain the program
`DMLTranslator`	`getDmlTranslator()`	Obtain the translator
`ExecutionContext`	`getExecutionContext()`	Obtain the execution context
`MLContext.ExecutionType`	`getExecutionType()`	Obtain the current execution environment.
`Program`	`getRuntimeProgram()`	Obtain the runtime program
`Script`	`getScript()`	Obtain the Script object associated with this ScriptExecutor
`boolean`	`isMaintainSymbolTable()`	Obtain whether or not all values should be maintained in the symbol table after execution.
`void`	`setConfig(DMLConfig config)`	Set the SystemDS configuration properties.
`void`	`setExecutionType(MLContext.ExecutionType executionType)`	Set the execution environment.
`void`	`setExplain(boolean explain)`	Whether or not an explanation of the DML/PYDML program should be output to standard output.
`void`	`setExplainLevel(MLContext.ExplainLevel explainLevel)`	Set the level of program explanation that should be displayed if explain is set to true.
`void`	`setForceGPU(boolean enabled)`	Whether or not to force GPU usage.
`void`	`setGPU(boolean enabled)`	Whether or not to enable GPU usage.
`void`	`setInit(boolean init)`	Whether or not to initialize the scratch_space, bufferpool, etc.
`void`	`setMaintainSymbolTable(boolean maintainSymbolTable)`	Set whether or not all values should be maintained in the symbol table after execution.
`void`	`setStatistics(boolean statistics)`	Whether or not statistics about the DML/PYDML program should be output to standard output.
`void`	`setStatisticsMaxHeavyHitters(int maxHeavyHitters)`	Set the maximum number of heavy hitters to display with statistics.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - ScriptExecutor
```
public ScriptExecutor()
```
    ScriptExecutor constructor.
  - ScriptExecutor
```
public ScriptExecutor(DMLConfig config)
```
    ScriptExecutor constructor, where the configuration properties are passed in.
    
    Parameters:
    
    config - the configuration properties to use by the ScriptExecutor
- Method Detail
  - compile
```
public void compile(Script script)
```
  - compile
```
public void compile(Script script,
                    boolean performHOPRewrites)
```
    Compile a DML or PYDML script. This will help analysis of DML programs that have dynamic recompilation flag set to false without actually executing it. This is broken down into the following primary methods:
    
    setup(Script)
    
    parseScript()
    
    liveVariableAnalysis()
    
    validateScript()
    
    constructHops()
    
    rewriteHops()
    
    rewritePersistentReadsAndWrites()
    
    constructLops()
    
    generateRuntimeProgram()
    
    showExplanation()
    
    countCompiledMRJobsAndSparkInstructions()
    
    initializeCachingAndScratchSpace()
    
    cleanupRuntimeProgram()
    Parameters:
    
    script - the DML or PYDML script to compile
    
    performHOPRewrites - should perform static rewrites, perform intra-/inter-procedural analysis to propagate size information into functions and apply dynamic rewrites
  - execute
```
public MLResults execute(Script script)
```
    Execute a DML or PYDML script. This is broken down into the following primary methods:
    
    compile(Script)
    
    createAndInitializeExecutionContext()
    
    executeRuntimeProgram()
    
    cleanupAfterExecution()
    Parameters:
    
    script - the DML or PYDML script to execute
    
    Returns:
    
    the results as a MLResults object
  - setConfig
```
public void setConfig(DMLConfig config)
```
    Set the SystemDS configuration properties.
    
    Parameters:
    
    config - The configuration properties
  - getDmlProgram
```
public DMLProgram getDmlProgram()
```
    Obtain the program
    
    Returns:
    
    the program
  - getDmlTranslator
```
public DMLTranslator getDmlTranslator()
```
    Obtain the translator
    
    Returns:
    
    the translator
  - getRuntimeProgram
```
public Program getRuntimeProgram()
```
    Obtain the runtime program
    
    Returns:
    
    the runtime program
  - getExecutionContext
```
public ExecutionContext getExecutionContext()
```
    Obtain the execution context
    
    Returns:
    
    the execution context
  - getScript
```
public Script getScript()
```
    Obtain the Script object associated with this ScriptExecutor
    
    Returns:
    
    the Script object associated with this ScriptExecutor
  - setExplain
```
public void setExplain(boolean explain)
```
    Whether or not an explanation of the DML/PYDML program should be output to standard output.
    
    Parameters:
    
    explain - true if explanation should be output, false otherwise
  - setStatistics
```
public void setStatistics(boolean statistics)
```
    Whether or not statistics about the DML/PYDML program should be output to standard output.
    
    Parameters:
    
    statistics - true if statistics should be output, false otherwise
  - setStatisticsMaxHeavyHitters
```
public void setStatisticsMaxHeavyHitters(int maxHeavyHitters)
```
    Set the maximum number of heavy hitters to display with statistics.
    
    Parameters:
    
    maxHeavyHitters - the maximum number of heavy hitters
  - isMaintainSymbolTable
```
public boolean isMaintainSymbolTable()
```
    Obtain whether or not all values should be maintained in the symbol table after execution.
    
    Returns:
    
    true if all values should be maintained in the symbol table, false otherwise
  - setMaintainSymbolTable
```
public void setMaintainSymbolTable(boolean maintainSymbolTable)
```
    Set whether or not all values should be maintained in the symbol table after execution.
    
    Parameters:
    
    maintainSymbolTable - true if all values should be maintained in the symbol table, false otherwise
  - setInit
```
public void setInit(boolean init)
```
    Whether or not to initialize the scratch_space, bufferpool, etc. Note that any redundant initialize (e.g., multiple scripts from one MLContext) clears existing files from the scratch space and buffer pool.
    
    Parameters:
    
    init - true if should initialize, false otherwise
  - setExplainLevel
```
public void setExplainLevel(MLContext.ExplainLevel explainLevel)
```
    Set the level of program explanation that should be displayed if explain is set to true.
    
    Parameters:
    
    explainLevel - the level of program explanation
  - setGPU
```
public void setGPU(boolean enabled)
```
    Whether or not to enable GPU usage.
    
    Parameters:
    
    enabled - true if enabled, false otherwise
  - setForceGPU
```
public void setForceGPU(boolean enabled)
```
    Whether or not to force GPU usage.
    
    Parameters:
    
    enabled - true if enabled, false otherwise
  - getConfig
```
public DMLConfig getConfig()
```
    Obtain the SystemDS configuration properties.
    
    Returns:
    
    the configuration properties
  - getExecutionType
```
public MLContext.ExecutionType getExecutionType()
```
    Obtain the current execution environment.
    
    Returns:
    
    the execution environment
  - setExecutionType
```
public void setExecutionType(MLContext.ExecutionType executionType)
```
    Set the execution environment.
    
    Parameters:
    
    executionType - the execution environment

Class ScriptExecutor

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ScriptExecutor

ScriptExecutor

Method Detail

compile

compile

execute

setConfig

getDmlProgram

getDmlTranslator

getRuntimeProgram

getExecutionContext

getScript

setExplain

setStatistics

setStatisticsMaxHeavyHitters

isMaintainSymbolTable

setMaintainSymbolTable

setInit

setExplainLevel

setGPU

setForceGPU

getConfig

getExecutionType

setExecutionType