【文章內(nèi)容簡(jiǎn)介】 c operate the java code for the pilation the procedure to provide the formidable function reflection, this function was JavaBeans is specially useful, the use reflected Java to be able to support the VB programmer to be familiar with the use the tool. procedure of analysis class ability is called the reflector, in Java to provide this function the package to call reflect reflection mechanism is extremely formidable. 1) when run analysis class ability. 2) when run searches observes a class of object. 3) realizes the general array operation code. 4) provides the method object. But this mechanism mainly aims at the tool but not the application and the procedure. In the reflection mechanism most important part is that permits class that you inspect structure. With to API includes: returns to the field. returns to the method. returns to the parameter. Method pointer: Java does not have the method pointer, makes a method address another method, may invoke it in behind, but the interface is the better solution. 23. interface: should showing class could do what but not to assign how to do, a class may realize one or many interfaces. interface is not a class, but is to conforms to a interface request class of set of standard. If realizes a interface to need 2 steps: 1) the statement class needs to realize assigns the interface. 2) provides in the interface all methods definition. Stated a class realizes a interface to need to use the implements key words Class actionB implements Comparable its actionb needs to provide the CompareTo method, the interface is not the class, cannot use a new example interface. class only then a super class, but a class can realize many interfaces. In a Java important interface: Cloneable interface and callback :to programs a monly used pattern is callback,in the pattern, you may refer when this class of pattern settled specific time occurs returns to adjusts on the object the method. Example:ActionListener interface monitor. Similar API includes: clone:The clone method is a object protection method, this meant your code cannot simple invoke it. class an inner class definition is the definition in another class. The reason is: 1) an inner class object can visit founds its object realization, including private data. 2) about other classes in the same package in that, inner class can be hided. 3) the anonymous inner class may the very convenient definition accent. In 4) uses the category to be possible the extremely convenient pilation event driver. class (proxy): 1) appointing all codes that interfaces request 2) all methods (toString equals) that object class define type:Java is kind of emphasizing type language, each variable all must be declared its types at first, in java altogether has 8 basic types . four kinds are the long, two kinds are the float, one is the char, being used in the Unicode code char, Boolean. 1. java is simple Java and C + + are very similar, but much simpler. All the highlevel programming language features, is not absolutely necessary have been deleted. For example, Java does not overload operator, the title of the document, preprocessing, puting pointer, the structure of the joint, multidimensional array, templates and implicit type conversion. If you know a little C, C + + or Pascal, you will soon master Java. Here is a simple procedure JavaHelloWorld: publicclassHelloInter ( publicstaticvoidmain (Stringargv []) ( System. out. println ( HelloInter!) ) ) 2. Java is objectoriented Java is an objectoriented programming language. In addition to the simple types, such as digital and Boolean operators in addition, Java is an object of most. As with any objectoriented languages, Java code also organized by category. Each category provides a definition of the object behavior. Another type of succession can be a kind of behavior. In the category of the root level, often the target category. Java support for the single type of inherited hierarchy. This means that each category can only inherit one other category. Some of the language to allow multiple inheritance, but it may cause confusion and unnecessarily plicated language. For example, imagine that an object would inherit two pletely different category. Java also supports the kind of summary of the interface. This allows programmers to define the interface methods, and do not have to rush immediately to determine the methods to achieve. A type of interface can be a number of purposes in order to truly multiinheritance of a number of advantages. The implementation of an object can be any number of interfaces. IDL interface and Java interface very similar. Very easy to set up IDLJ piler. In other words, Java can be used to create a CORBA object system distributed object system. In the view of many puter systems use IDL interface and