ClosureCleaner (Flink : Core 2.2.0 API)

java.lang.Object
- org.apache.flink.api.java.ClosureCleaner

```
@Internal
public class ClosureCleaner
extends Object
```
The closure cleaner is a utility that tries to truncate the closure (enclosing instance) of non-static inner classes (created for inline transformation functions). That makes non-static inner classes in many cases serializable, where Java's default behavior renders them non-serializable without good reason.

Constructor Summary

Constructors
Constructor Description

ClosureCleaner()

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static void`	`clean(Object func, ExecutionConfig.ClosureCleanerLevel level, boolean checkSerializable)`	Tries to clean the closure of the given object, if the object is a non-static inner class.
`static void`	`ensureSerializable(Object obj)`

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

- Constructor Detail
  - ClosureCleaner
```
public ClosureCleaner()
```
- Method Detail
  - clean
```
public static void clean(Object func,
                         ExecutionConfig.ClosureCleanerLevel level,
                         boolean checkSerializable)
```
    Tries to clean the closure of the given object, if the object is a non-static inner class.
    
    Parameters:
    
    func - The object whose closure should be cleaned.
    
    level - the clean up level.
    
    checkSerializable - Flag to indicate whether serializability should be checked after the closure cleaning attempt.
    
    Throws:
    
    InvalidProgramException - Thrown, if 'checkSerializable' is true, and the object was not serializable after the closure cleaning.
    
    RuntimeException - A RuntimeException may be thrown, if the code of the class could not be loaded, in order to process during the closure cleaning.
  - ensureSerializable
```
public static void ensureSerializable(Object obj)
```