xsl本身就是一个构型良好的xml，它能够把一个xml文档转换成另外一个xml文档，或者转换成文本文件、html文件等等。这里就是利用xsl来动态的生成我们想要的java文件（从某种角度看，java代码其实也就是一个文本文件），希望能够通过这篇文章，看到xml以及相关的技术所具有的强大能力！

这里首先给一个xml例子，我们将通过一个xsl从该xml文件中抽取有用的信息来生成java代码（实际上是一个javabean）：

[code]

Product

This bean represents a product that the company

offers to its customers

code

int

the product inventory code

name

String

the product name

testedOnAnimals

boolean

the flag that indicates if the product was

tested on animals

availableSince

java.util.Date

the date when the company started offering this

product to its customers

[/code]

下面我就直接给出转换的xsl，如果大家对xsl不是很了解的话，可以先看一些资料，了解之后就会明白了。我在里面稍微做了些注释：

[code]

xmlns:xsl="http://www.w3.org/1999/XSL/Transform"

version="1.0"

xmlns:java="http://xml.apache.org/xslt/java"

exclude-result-prefixes="java">

/**

* //这里是获取xml文档中的节点值

* This class has been generated by the XSLT processor from the

metadata

*/

public class {

/**

* Creates a new instance of the

select="name"/> bean

*/

public () {}

}

private

//输出文本，这里是输出一个空格

;

//定义xsl中要使用的变量

//这里使用了xslt extensions，它可以允许在xslt中直接引用java中方法，非常方便。

/**

* Sets

* @param is

select="comments"/>

*/

public void set(

of select="type"/>

of select="name"/>) {

this. =

select="name"/>;

}

/**

* Returns

* @return

*/

public

select="$cname"/>() {

return ;

}

is

get

[/code]

好了，完成以上工作之后，只要在cmd中，输入如下的命令行，就可以获得我们想要的结果了：

java org.apache.xalan.xslt.Process -in xmlSource -xsl stylesheet -out outputfile

这里列出结果：

[code]

/**

* This bean represents a product that the company offers to its

customers

* This class has been generated by the XSLT processor from the

metadata

*/

public class Product {

/**

* Creates a new instance of the Product bean

*/

public Product() {}

private int code;

/**

* Sets the product inventory code

* @param code is the product inventory code

*/

public void setCode(int code) {

this.code = code;

}

/**

* Returns the product inventory code

* @return the product inventory code

*/

public int getCode() {

return code;

}

private String name;

/**

* Sets the product name

* @param name is the product name

*/

public void setName(String name) {

this.name = name;

}

/**

* Returns the product name

* @return the product name

*/

public String getName() {

return name;

}

private boolean testedOnAnimals;

/**

* Sets the flag that indicates if the product was tested on animals

* @param testedOnAnimals is the flag that indicates if the product

was tested on animals

*/

public void setTestedOnAnimals(boolean testedOnAnimals) {

this.testedOnAnimals = testedOnAnimals;

}

/**

* Returns the flag that indicates if the product was tested on

animals

* @return the flag that indicates if the product was tested on

animals

*/

public boolean isTestedOnAnimals() {

return testedOnAnimals;

}

private java.util.Date availableSince;

/**

* Sets the date when the company started offering this product to

its customers

* @param availableSince is the date when the company started

offering this product to its customers

*/

public void setAvailableSince(java.util.Date availableSince) {

this.availableSince = availableSince;

}

/**

* Returns the date when the company started offering this product

to its customers

* @return the date when the company started offering this product

to its customers

*/

public java.util.Date getAvailableSince() {

return availableSince;

}

}

[/code]

总结：

1. 在熟悉了xsl的基本使用之后，理解以上的内容并不是困难；

2. 这样做是比较适合预先知道了某些逻辑功能，但由于某种原因，需要动态生成，或者是为了节省不必要的重复工作，可以通过它自动生成代码；

3. 修改这个xsl比较方便。

sjoy