com.facebook.buck.util

Class CloseableMemoizedSupplier<T>

java.lang.Object

com.facebook.buck.util.AbstractCloseableMemoizedSupplier<T,RuntimeException>

com.facebook.buck.util.CloseableMemoizedSupplier<T>

All Implemented Interfaces:

AutoCloseable, java.util.function.Supplier<T>

public class CloseableMemoizedSupplier<T>
extends AbstractCloseableMemoizedSupplier<T,RuntimeException>

Convenience wrapper class to attach closeable functionality to suppliers of resources to be closed. Suppliers will be memoized such that the resources are only closed if we have requested them.

Example:

 class Main {
  public static void main() {
    try (CloseableMemoizedSupplier<Resource> closeableSupplier =
        CloseableMemoizedSupplier.of(Resource::new, resource::shutDown)) {
      if (condition) {
        useResource(closeableSupplier.get())
      }
    }
  }
 }

 

The above will only construct the Resource if condition is true, and close the constructed resource appropriately.

Method Summary

Modifier and Type	Method and Description
static <T,E extends Exception> CloseableMemoizedSupplier<T>	of(java.util.function.Supplier<T> supplier, java.util.function.Consumer<T> closer) Wrap a supplier with AutoCloseable interface and close only if the supplier has been used.

Methods inherited from class com.facebook.buck.util.AbstractCloseableMemoizedSupplier

close, get

Methods inherited from class java.lang.Object

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

Method Detail

of

public static <T,E extends Exception> CloseableMemoizedSupplier<T> of(java.util.function.Supplier<T> supplier,
                                                                      java.util.function.Consumer<T> closer)

Wrap a supplier with AutoCloseable interface and close only if the supplier has been used. Close is idempotent.

Parameters:

supplier - the Supplier of a resource to be closed

closer - the method to close the resource