org.apache.commons.jexl3.internal.introspection
Class ConstructorMethod

java.lang.Object
  org.apache.commons.jexl3.internal.introspection.ConstructorMethod

All Implemented Interfaces:

JexlMethod

public final class ConstructorMethod
extends Object
implements JexlMethod

A JexlMethod that wraps a constructor.

discover

public static ConstructorMethod discover(Introspector is,
                                         Object ctorHandle,
                                         Object... args)

Discovers a class constructor and wrap it as a JexlMethod.

Parameters:

is - the introspector

ctorHandle - a class or class name

args - constructor arguments

Returns:

a JexlMethod

invoke

public Object invoke(Object obj,
                     Object... params)
              throws Exception

Description copied from interface: JexlMethod

Invocation method, called when the method invocation should be performed and a value returned.

Specified by:

invoke in interface JexlMethod

Parameters:

obj - the object

params - method parameters.

Returns:

the result

Throws:

Exception - on any error.

tryInvoke

public Object tryInvoke(String name,
                        Object obj,
                        Object... params)

Description copied from interface: JexlMethod

Attempts to reuse this JexlMethod, checking that it is compatible with the actual set of arguments. Related to isCacheable since this method is often used with cached JexlMethod instances.

Specified by:

tryInvoke in interface JexlMethod

Parameters:

name - the method name

obj - the object to invoke the method upon

params - the method arguments

Returns:

the result of the method invocation that should be checked by tryFailed to determine if it succeeded or failed.

tryFailed

public boolean tryFailed(Object rval)

Description copied from interface: JexlMethod

Checks whether a tryInvoke return value indicates a failure or not.

Usage is : Object r = tryInvoke(...); if (tryFailed(r) {...} else {...}

Specified by:

tryFailed in interface JexlMethod

Parameters:

rval - the value returned by tryInvoke

Returns:

true if tryInvoke failed, false otherwise

isCacheable

public boolean isCacheable()

Description copied from interface: JexlMethod

Specifies if this JexlMethod is cacheable and able to be reused for this class of object it was returned for.

Specified by:

isCacheable in interface JexlMethod

Returns:

true if can be reused for this class, false if not

getReturnType

public Class<?> getReturnType()

Description copied from interface: JexlMethod

returns the return type of the method invoked.

Specified by:

getReturnType in interface JexlMethod

Returns:

return type