什么是JavaBean

Javabean 就是一个类，这个类就定义一系列 get<Name> 和 set<Name> 方法。 So simple ！
Javabean 就是为了和 jsp 页面传数据化简交互过程而产生的值对象。

使用 javabean 和不用 javabean 的区别：
一个 javabean 就是为 jsp 页面上的元素一一开辟一个空间，然后根据需要赋值、读值。而如果不用 javabean ，就直接使用 HttpServlet 的 request 对象：只在 jsp 页面间传递获取数据：
String name=req.getParameter(“name”);

再来段英文解释：
JavaBeans are reusable software components for Java that can be manipulated visually in a builder tool. Practically, they are classes written in the Java programming language  conforming to a particular convention. They are used to encapsulate many objects into a single object (the bean), so that they can be passed around as a single bean object instead of as multiple individual objects. A JavaBean is a Java Object that is serializable, has a nullary constructor, and allows access to properties using getter and setter methods.

下面的例子就是一个JavaBean:

/**
 * Class <code>DemoBean</code>.
 */
public class DemoBean implements java.io.Serializable {
 
    private String name;
 
    private boolean deceased;
 
    /** No-arg constructor (takes no arguments). */
    public PersonBean() {
    }
 
    /**
     * Property <code>name</code> (note capitalization) readable/writable.
     */
    public String getName() {
        return this.name;
    }
 
    /**
     * Setter for property <code>name</code>.
     * @param name
     */
    public void setName(final String name) {
        this.name = name;
    }
 
    /**
     * Getter for property "deceased"
     * Different syntax for a boolean field (is vs. get)
     */
    public boolean isDeceased() {
        return this.deceased;
    }
 
    /**
     * Setter for property <code>deceased</code>.
     * @param deceased
     */
    public void setDeceased(final boolean deceased) {
        this.deceased = deceased;
    }
}

评论

1 楼 hekai1990 2012-04-25  

受教了......