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public class: Statement [javadoc | source]

Direct Known Subclasses:

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.
Field Summary
static  ExceptionListener defaultExceptionListener     
 ClassLoader loader     
 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 {@code target} and the {@code methodName} values should not be {@code null}. Otherwise an attempt to execute this {@code Expression} will result in a {@code NullPointerException}. If the {@code arguments} value is {@code null}, an empty array is used as the value of the {@code arguments} property.

    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 from java.beans.Statement Summary:
execute,   getArguments,   getMethod,   getMethodName,   getTarget,   instanceName,   invoke,   toString
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from java.beans.Statement Detail:
 public  void execute() throws Exception 
    The {@code execute} method finds a method whose name is the same as the {@code 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 java.lang.reflect.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 {@code Expression}s rather than {@code Statement}s as they return a value.
    • The method names "get" and "set" defined in the java.util.List interface may also be applied to array instances, mapping to the static methods of the same name in the {@code Array} class.
 public Object[] getArguments() 
    Returns the arguments for the method to invoke. The number of arguments and their types must match the method being called. {@code null} can be used as a synonym of an empty array.
 static Method getMethod(Class<?> type,
    String name,
    Class<?> args) 
 public String getMethodName() 
    Returns the name of the method to invoke. If this method returns {@code null}, the #execute method throws a {@code NullPointerException}.
 public Object getTarget() 
    Returns the target object of this statement. If this method returns {@code null}, the #execute method throws a {@code NullPointerException}.
 String instanceName(Object instance) 
 Object invoke() throws Exception 
 public String toString() 
    Prints the value of this statement using a Java-style syntax.