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Java in a Nutshell

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The java.beans Package
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23.3 java.beans.Beans (JDK 1.1)

The Beans class is never meant to be instantiated; its static methods provide miscellaneous JavaBeans features.

The instantiate() method creates an instance of a bean. The specified bean name represents either a serialized bean file or a bean class file; it is interpreted relative to the specified ClassLoader object.

The setDesignTime() and isDesignTime() methods are used to set and query a flag that indicates whether beans are being used in an application builder environment. Similarly, setGuiAvailable() and isGuiAvailable() set and query a flag that indicates whether the Java Virtual Machine is running in an environment in which a GUI is available. (Note that untrusted applet code cannot call setDesignTime() or setGuiAvailable().)

The isInstanceOf() method is a replacement for the Java instanceof operator for use with beans. Currently, it behaves just like instanceof, but in the future it may work with beans that consist of a set of Java objects, each of which provides a different "view" of a bean. Similarly, the getInstanceOf() method is a replacement for the Java cast operator. It converts a bean to a superclass or interface type. Currently, it behaves just like a cast, but you should use it for future compatibility with multiclass beans.

public class Beans extends Object {
    // Default Constructor: public Beans()
    // Class Methods
            public static Object getInstanceOf(Object bean, Class targetType);
            public static Object instantiate(ClassLoader cls, String beanName)
            public static Object instantiate'u'throws IOException, ClassNotFoundException;
            public static boolean isDesignTime();
            public static boolean isGuiAvailable();
            public static boolean isInstanceOf(Object bean, Class targetType);
            public static void setDesignTime(boolean isDesignTime) throws SecurityException;
            public static void setGuiAvailable(boolean isGuiAvailable) throws SecurityException;
}


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