## org.springframework.aop.target
Class HotSwappableTargetSource

    java.lang.Object
      org.springframework.aop.target.HotSwappableTargetSource

All Implemented Interfaces:
  Serializable, TargetClassAware, TargetSource

    public class HotSwappableTargetSource

extends Object
implements TargetSource, Serializable

`TargetSource` implementation that caches a local target object, but allows the target to be swapped while the application is running.

If configuring an object of this class in a Spring IoC container, use constructor injection.

This TargetSource is serializable if the target is at the time of serialization.

Author:
  Rod Johnson, Juergen Hoeller
See Also:
  Serialized Form

Constructor Summary
`HotSwappableTargetSource(Object initialTarget)` Create a new HotSwappableTargetSource with the given initial target object.

Method Summary
`boolean` `equals(Object other)` Two HotSwappableTargetSources are equal if the current target objects are equal.
`Object` `getTarget()` Return a target instance.
`Class<?>` `getTargetClass()` Return the type of the current target object.
`int` `hashCode()`
`boolean` `isStatic()` Will all calls to `TargetSource.getTarget()` return the same object?
`void` `releaseTarget(Object target)` Release the given target object obtained from the `TargetSource.getTarget()` method.
`Object` `swap(Object newTarget)` Swap the target, returning the old target object.
`String` `toString()`

Methods inherited from class java.lang.Object
`clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

Constructor Detail

### HotSwappableTargetSource

    public HotSwappableTargetSource(Object initialTarget)

  Create a new HotSwappableTargetSource with the given initial target object.

  Parameters:
    `initialTarget` - the initial target object

Method Detail

### getTargetClass

    public Class<?> getTargetClass()

  Return the type of the current target object.

  The returned type should usually be constant across all target objects.

  Specified by:
    `getTargetClass` in interface `TargetClassAware`
  Specified by:
    `getTargetClass` in interface `TargetSource`
  Returns:
    the type of targets returned by this `TargetSource`

### isStatic

    public final boolean isStatic()

  Description copied from interface: `TargetSource`
  Will all calls to `TargetSource.getTarget()` return the same object?

  In that case, there will be no need to invoke `TargetSource.releaseTarget(Object)`, and the AOP framework can cache the return value of `TargetSource.getTarget()`.

  Specified by:
    `isStatic` in interface `TargetSource`
  Returns:
    `true` if the target is immutable
  See Also:
    `TargetSource.getTarget()`

### getTarget

    public Object getTarget()

  Description copied from interface: `TargetSource`
  Return a target instance. Invoked immediately before the AOP framework calls the "target" of an AOP method invocation.

  Specified by:
    `getTarget` in interface `TargetSource`
  Returns:
    the target object, which contains the joinpoint

### releaseTarget

    public void releaseTarget(Object target)

  Description copied from interface: `TargetSource`
  Release the given target object obtained from the `TargetSource.getTarget()` method.

  Specified by:
    `releaseTarget` in interface `TargetSource`
  Parameters:
    `target` - object obtained from a call to `TargetSource.getTarget()`

### swap

    public Object swap(Object newTarget)
                throws IllegalArgumentException

  Swap the target, returning the old target object.

  Parameters:
    `newTarget` - the new target object
  Returns:
    the old target object
  Throws:
    `IllegalArgumentException` - if the new target is invalid

### equals

    public boolean equals(Object other)

  Two HotSwappableTargetSources are equal if the current target objects are equal.

  Overrides:
    `equals` in class `Object`

### hashCode

    public int hashCode()

  Overrides:
    `hashCode` in class `Object`

### toString

    public String toString()

  Overrides:
    `toString` in class `Object`