Statement (Java SE 17 & JDK 17)
Description: declaration: module: java.desktop, package: java.beans, class: Statement
Keywords: java.beans.Statement class

Module java.desktop
Package java.beans

# Class Statement

java.lang.Object
java.beans.Statement

Direct Known Subclasses:
  `Expression`

public class Statement extends Object
A `Statement` object represents a primitive statement in which a single method is applied to a target and a set of arguments - as in `"a.setFoo(b)"`. Note that where this example uses names to denote the target and its argument, a statement object does not require a name space and is constructed with the values themselves. The statement object associates the named method with its environment as a simple set of values: the target and an array of argument values.

Since:
  1.4

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Statement(Object target, String methodName, Object[] arguments)`
  Creates a new `Statement` object for the specified target object to invoke the method specified by the name and by the array of arguments.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `execute()`
  The `execute` method finds a method whose name is the same as the `methodName` property, and invokes the method on the target.
  `Object[]`
  `getArguments()`
  Returns the arguments for the method to invoke.
  `String`
  `getMethodName()`
  Returns the name of the method to invoke.
  `Object`
  `getTarget()`
  Returns the target object of this statement.
  `String`
  `toString()`
  Prints the value of this statement using a Java-style syntax.

  ### Methods declared in class java.lang.Object

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

- ## Constructor Details

  - ### Statement

    @ConstructorProperties({"target","methodName","arguments"}) public Statement(Object target, String methodName, Object[] arguments)
    Creates a new `Statement` object for the specified target object to invoke the method specified by the name and by the array of arguments.

    The `target` and the `methodName` values should not be `null`. Otherwise an attempt to execute this `Expression` will result in a `NullPointerException`. If the `arguments` value is `null`, an empty array is used as the value of the `arguments` property.

    Parameters:
      `target` - the target object of this statement
      `methodName` - the name of the method to invoke on the specified target
      `arguments` - the array of arguments to invoke the specified method

- ## Method Details

  - ### getTarget

    public Object getTarget()
    Returns the target object of this statement. If this method returns `null`, the `execute()` method throws a `NullPointerException`.
    Returns:
      the target object of this statement

  - ### getMethodName

    public String getMethodName()
    Returns the name of the method to invoke. If this method returns `null`, the `execute()` method throws a `NullPointerException`.
    Returns:
      the name of the method

  - ### getArguments

    public Object[] getArguments()
    Returns the arguments for the method to invoke. The number of arguments and their types must match the method being called. `null` can be used as a synonym of an empty array.
    Returns:
      the array of arguments

  - ### execute

    public void execute() throws Exception
    The `execute` method finds a method whose name is the same as the `methodName` property, and invokes the method on the target. When the target's class defines many methods with the given name the implementation should choose the most specific method using the algorithm specified in the Java Language Specification (15.11). The dynamic class of the target and arguments are used in place of the compile-time type information and, like the `Method` class itself, conversion between primitive values and their associated wrapper classes is handled internally.

    The following method types are handled as special cases:

    - Static methods may be called by using a class object as the target.
    - The reserved method name "new" may be used to call a class's constructor as if all classes defined static "new" methods. Constructor invocations are typically considered `Expression`s rather than `Statement`s as they return a value.
    - The method names "get" and "set" defined in the `List` interface may also be applied to array instances, mapping to the static methods of the same name in the `Array` class.
    Throws:
      `NullPointerException` - if the value of the `target` or `methodName` property is `null`
      `NoSuchMethodException` - if a matching method is not found
      `SecurityException` - if a security manager exists and it denies the method invocation
      `Exception` - that is thrown by the invoked method
    See Also:
      - `Method`

  - ### toString

    public String toString()
    Prints the value of this statement using a Java-style syntax.
    Overrides:
      `toString` in class `Object`
    Returns:
      a string representation of the object.