今天天气好晴朗处处好风光,好天气好开始,图老师又来和大家分享啦。下面给大家推荐在JavaScript程序中整合Java函数,希望大家看完后也有个好心情,快快行动吧!
【 tulaoshi.com - 编程语言 】
问题的提出: 假定我们的Html 页中有一些表单需要处理,并且我们需要初始化数据库中的字段,我们该怎么办?标准的解决办法就是使用CGI脚本或是使用Java Servlet等服务器端程序,但是你有没有想过,还可以编写一个脚本程序使你可以用javascript直接调用服务器端Java程序进行任何计算的结果,就像下面代码中列的那样:
<html>
我们的表单<br>
<form>
<input type="text" name="textField"><br>
<input type="button" value="Click" onClick="updateField();">
</form>
<script>
function updateField()
{
document.forms[0].textField.value=java.dbConnection.getData('SQL_eXPr');
}
</script>
</html>
所以,当用户点击按钮,该程序就会调用Java的dbConnection类,然后就可以在JavaScript应用程序中使用Java返回的结果了。上面的程序只是更新了textField的值,我们不必刷新整个页面。由于这个程序也不是jsp文件,所以不必把你的页面编译成Java Servlet。
你还可以使用调用某些Java函数返回的结果替代段落中的文字;在一个非常大的HTML表中,你可以使用同样的方法,只要更新一行信息:
<script language="JavaScript">
function changeCol()
{
document.all.quote.rows[0].cells[1].innerText=java.Stock.getQuote('Wayne');
}
</script>
<table id="quote" border=1>
<tr><td>Wayne</td><td>123</td></tr>
<tr><td>Another one</td><td>34</td></tr>
</table>
怎么样,能够直接在JavaScript中嵌入Java对象的调用,而且可以保证你的页面的其它部分不会被改变,你一定对这个问题比较感爱好吧。好吧,现在就让我们用Java Servlet来实现它吧。
工作原理
我的构思是使用Java Servlet编写一个JinJ(Java in JavaScript)程序,能够让 HTML 页面内整合 Java 类和 JavaScript脚本,将所有使用JavaScript调用Java函数的HTML页面都传送到这个Servlet中处理,JinJ将即时产生带有Java applet的隐藏帧,
这个applet起着桥梁的作用,用来和Java通讯,它的大小还不到2KB,为了调用对象,Applet使用HTTP连接同一个JinJ Servlet。JinJ用相应的JavaScript结构来替换所有的Java调用(其实每一个调用前都有前缀java),并且保持页面的其它部分不变。所以,为了能够让JinJ正确识别,你的JavaScript代码中的任何Java调用,都要使用如下的结构: java.object_name.function_name(list_of_parameters) 其中:
java:是一个标准的前缀:
object_name:是一个变量名,保存某些Java类的实例(在后面,我们会具体的探讨如何创建/定义这样的变量),比如说它可以是一个类名。
function_name:是一个Java类的函数名。
list_of_parameters:是调用的函数的参数列表(可以为空)。
下面也将会探讨如何把参数传给Java,每个参数显然是某个JavaScript表达式。你也可以使用预编译页,换句话说就是在使用HTML页面之前编译它。
服务器实现
在谈编程之前我还想说一说JinJ的服务器实现。在你的服务器中需要两个组成部分:JINJ servlet和bridge applet.。你所有需要被整合的HTML页面都是被JinJ servlet预处理,你可以通过以下方法实现:
a)把你的页面当作一个参数传递给JinJ servlet
所以你可以把你HTML页中如下的超链接<a href="mypage.html">我的页面</a>改为:<a href="http://myhost/servlet/JinJ?mypage.html" target="_top">我的页面</a>
JinJ servlet 随即把所有的Java调用转化成JavaScript,然后产生页面并输出出来。
b)定义某种映射。举例来说,这里我们设置Servlet调用扩展名为.JinJ的文件 (这里介绍的方法针对运行于NT上的JSWDK,你所使用的Servelt系统的具体定义映射的方法请参看你的用户指南)
JinJ.code=JinJ
JinJ.initparams=servlet=http://myhost/servlet/JinJ,
root=c:jswdkwebpages,
objects=c:jswdkobj.txt,
codebase=http://myhost/
设置了以后,你就可以使用http://myhost/some_file.JinJ然后JinJ servlet将会自动被调用了
Servlet参数
为了让JinJ正常运行,还应当能够为JinJ servlet设置一些全局参数,这也是我们在编程是应当注重到的问题。对于JSWDK, Servlet属性是参数'initparams'的一部分;对于Tomcat,则应当编辑系统中的web.XML
1)需要设置JinJ servlet的路径,参数名是servlet,就像这样:
http://your_host:port/servlet/JINJ
2) 需要设置存放HTML页的根目录,参数名是root,其值就像这样: /home/webpages (或c:webpages) (默认值是一个空的字符串)。 例如,假如你的根目录是:/home/webpages,并且你使用http://host/servlet/JINJ?myfile.htm 的话,那你的真实的文件名是/home/webpages/myfile.htm
3) 需要设置你定义的Java对象的文件的完全目录,参数名是objects,其值只是一个存放在你的服务器中的一个文件的文件名。
4) 需要设置用于java applet的codebase,参数名是codebase,定义了存放applet的类的路径,比如http://your_host/ 。
以下为Tomcat中web.xml 中的相应设置:
<servlet>
<servlet-name>JinJ</servlet-name>
<servlet-class>JinJ</servlet-class>
<init-param>
<param-name>servlet</param-name>
<param-value>http://your_host/servlet/JinJ</param-value>
</init-param>
<init-param>
<param-name>root</param-name>
<param-value>path_to_the_root_Directory</param-value>
</init-param>
<init-param>
<param-name>objects</param-name>
<param-value>path_to_your_objects_file</param-value>
</init-param>
<init-param>
<param-name>codebaset</param-name>
<param-value>http://your_host/</param-value>
</init-param>
</servlet>
在编程时还应当注重实现读取对象文件中所包含的对象,或创建新的Java对象
1. 在初始化JinJ Servlet时将创建一些Java对象,因此你必须在某个文本文件中定义这些对象,并且在参数objects中设置这个文件的路径,这是一个文本文件,每一行描述了一个元素(空行和以#或//开头的行将被忽略),使用下面的格式来描述参数:
object_name=new class_name(list_of_parameters);
换句话说,它很象每次调用类构造器的new操作符,object_name 是就是某个你将在JavaScript中使用到的标识符,例如:
file://数据池
A=new dbPool(5);
file://哈希表
B=new java.util.Hashtable();
或者使用你自己定义的包和类:c=new myPackage.myClass(true);
然后在JavaScript中,你就可以使用它们了,如A.connect(),其中connect() 是类dbPool的一个函数,或者使用B.put('key',value)
注重:
1)你的类应当放在你的CLASSPATH指定的目录下面。
2)你可以使用类名作为对象名 (不过这必须在没有重名的情况下,因为对象名必须是唯一的),如:dbPool=new dbPool();
(本文来源于图老师网站,更多请访问http://www.tulaoshi.com/bianchengyuyan/)2. 为了更优化程序,应当在编程的时候就预建一些对象组成标准化库,通过标准化库,你可以在运行中创建/删除对象的实例,查看存在的对象等。
下面就是我们需要实现的标准化库(预定义的对象) ,对象名是JinJ,所以服务器端名为JinJ的实例将会被自动创建,这给类中有下面几个函数:
public boolean create(String object_name,String class_name,list_of_constrUCtors_parameters);
public void delete(String object_name);
public boolean exists(String object_name);
public String id();
public int random(int n1, int n2);
public String rewriteURL(document,String id_name);
public String rewriteURL(document,String id_name,String id_value);
create(创建):能够让你在运行时创建某个对象的实例:
参数为:
- 新的对象名
- 类名
- 参数列表 (假如你使用默认构造函数的时候,可以为空)。
返回值:
- 根据创建的接过返回true 或 false
例如:
<script language="JavaScript">
<!--创建myHash 作为一个新的哈希表Hashtable -->
java.JinJ.create("myHash","java.util.Hashtable");
<!-- 使用myHash -->
java.myHash.put('key1','shop1');
</script>
delete:让你删除任何对象的实例。
参数为:
- 对象名
例如:
<script language="JavaScript">
<!-- 删除myHash -->
java.JinJ.delete("myHash");
</script>
exists:查看对象的实例是否存在。
参数为:
- 对象名
返回值:
true 或 false
例如:
<script language="JavaScript">
if (java.JinJ.exists("myHash")=='false')
{
<!--创建myHash 作为一个新的哈希表Hashtable -->
java.JinJ.create(myHash,"java.util.Hashtable");
<!--使用myHash -->
java.myHash.put('key1','shop1');
}
</script>
id: 返回唯一的标示符,比如你可以在支持session的程序中使用这个函数。
Random: 从给定的数域中返回随机值:
例如:
<script language="JavaScript">
var sessionId=java.JinJ.id();
<!-- 从1到10中的随机数 -->
var randValue=java.JinJ.random(1,10);
</script>
rewriteURL:能够让你使用session。你可以用<a href="some_url? id_name=id_value">你的链接</a>来替代<a href="some_url">你的链接</a>这同样适用于任何形式的动作。你可以只设置一个参数名,参数值将自动生成,也可以同时设置参数名和参数值:
例如:
<script language="JavaScript">
<!--添加sessionId=某个值到这个链接 -->
java.JinJ.rewriteURL(document,'sessionId');
<!-- 添加 id=12345 到这个链接-->
java.JinJ.rewriteURL(document,'id',12345);
</script>
我们还要能够分析读入Java函数的参数,对于一个参数我们必须知道它的数据类型,为了简单起见,我们就认为有四种数据类型整型,浮点型,布尔型其余的全归于字符串型,你可以看到,这在程序中都有相应的解释。
例如:
<!-- 我们假定A(int,float,String,boolean) -->
java.myClass.myFunc(2, 5.6, a123, true);
为了保证你传递的参数是一个字符串型的值的话,请你使用"或者',如:
<!--总是作为字符串型数据传递-->
java.myClass.myFunc("256");
函数返回的结果问题
假如Java函数的类型为void的话,那么将返回给JavaScript一个空字符串,在别的情况下(假如不是数组),将返回Java对象的字符型返回值。假如你的Java函数返回数组或者向量(Vector)或枚举(Enumeration),结果将被表示为JavaScript中的数组。例如:在类dbpool中,你假如有某个函数performQuery(some_sql_string)来通过JDBC来调用SQL查询,将转换ResultSet成为数组(或向量)然后把这个数组返回给JavaScript。
res=java.dbpool.performQuery("select * from emp");
first=res[0];
second=res[1];
程序还应该实现控制台(JINJ控制台),这样你就可以直接从浏览器中运行这个Servlet,并且可以创建/删除对象,相应的命令是: http://your_host/servlet/JINJ?your_password
或者,假如你使用扩展名映射JinJ的话,则::
http://your_host/your_file.JinJ?your_password ,这些都应当在程序中体现,你可以在servlet的初始化参数中设置口令,参数名是admin. 如:
JINJ.code=JINJ
JINJ.initparams=admin=secret,
servlet=http://myhost/servlet/JINJ,
root=/home/www/pub,
objects=/home/load/obj.txt,
codebase=http://myhost/
默认的密码值是abcd,所以使用JINJ?abcd 将运行治理员界面,通过这一页,你可以删除或者创建新的对象的实例。
下面,然我们来看看具体在Java代码上如何实现我们的构思:
JinJ.java
import java.io.*;
import java.lang.reflect.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class JinJ extends HttpServlet
{ public JinJ()
{
}
public void init(ServletConfig servletconfig)//初始化
throws ServletException
{
super.init(servletconfig);
inst = new Hashtable();
cls = new Hashtable();
NEWLINE = System.getProperty("line.separator"); file://获取行分割符在本系统中的属性值,例如在UNIX下为
separator = System.getProperty("file.separator");//获取文件分割符在本系统中的属性值,例如在UNIX下为/
if((THIS_SERVLET = getInitParameter("servlet")) == null)
file://getInitParameter方法,返回一个字符串,包含命名的初始化参数的值,假如参数不存在则为空。
THIS_SERVLET = "";
if((admin = getInitParameter("admin")) == null)
admin = "abcd";
if((DOCUMENT_ROOT = getInitParameter("root")) == null)
DOCUMENT_ROOT = "";
if(DOCUMENT_ROOT.length() > 0 && !DOCUMENT_ROOT.endsWith(separator))
file://假如DOCUMENT_ROOT的长度为正值,并且不以文件分割符结尾则
DOCUMENT_ROOT = DOCUMENT_ROOT + separator;
if((CODEBASE = getInitParameter("codebase")) == null)
CODEBASE = "";
JAVA_FILE = getInitParameter("objects");
if(JAVA_FILE != null && inst != null)
loadJava(JAVA_FILE);
}
private void loadJava(String s)
{
System.out.println("从" + s +"调用Java对象 ");
try
{
BufferedReader bufferedreader = new BufferedReader(new InputStreamReader(new FileInputStream(s)));
file://创建一个文件输入流缓冲区
String s1;
file://开始分析文件
while((s1 = bufferedreader.readLine()) != null)//每次读入一行
{
s1 = s1.trim(); file://把字符串两端的空格去掉
/*********************************************************
* 假如以";"结尾则去掉";"
**********************************************************/
if(s1.endsWith(";"))
s1 = s1.substring(0, s1.length() - 1).trim();
/*****************************************************************************
* 假如s1的长度大于零,并且第一个字符不为#和//,则调用processLine处理这一行参数
******************************************************************************/
if(s1.length() > 0 && s1.charAt(0) != '#' && !s1.startsWith("//"))
processLine(s1);
}
bufferedreader.close();
return;
}
catch(Exception _ex)
{
return;
}
}
private void processLine(String s)
{
/**************************************************************************
*取得这一行中第一次出现等号的下标值,假如没出现等号则返回-1
*假如没有等号,则输出错误信息
**************************************************************************/
int i = s.indexOf("=");
if(i <= 0 i == s.length() - 1)
{
System.out.println("不能处理此行信息: " + s);
return;
}
String s1 = s.substring(0, i).trim();//s1为s中等号前的字符串
String s2 = s.substring(i + 1).trim();//s2为s中等号后的字符串
if(s2.startsWith("new "))//判定s2是否以new开头,如new class_name(list_of_parameters);
s2 = s2.substring("new".length()).trim();
if(s1.length() == 0 s2.length() == 0)
{
System.out.println("不能处理此行信息: " + s);
return;
}
if(inst.get(s1) != null) file://为了防止重复定义类名
{
System.out.println("重复命名 " + s1);
return;
}
i = s2.indexOf("(");
if(i <= 0 && !s2.endsWith(")"))
{
System.out.println("不能处理此行信息:" + s);
return;
}
String s3 = s2.substring(0, i).trim();//s3为新定义的类名
s2 = s2.substring(i + 1, s2.length() - 1).trim();//s2为参数列表
if(inst.size() < 5)
processLine1(s1, s3, s2, s);
}
private String prepareString(String s)
{
if(s == null)
return null;
if(s.length() < 2)
return s;
if(s.charAt(0) == '"' && s.charAt(s.length() - 1) == '"') file://假如字符串s以"开头,又以"结尾,则把两头的"去掉
return s.substring(1, s.length() - 1);
if(s.startsWith("'") && s.endsWith("'"))//假如字符串s以'开头,又以'结尾,则把两头的"去掉
return s.substring(1, s.length() - 1);
else
return s;
}
private boolean processLine1(String s, String s1, String s2, String s3)
{ file://创建一个Object类的实例
Object obj[] = {
null, null
};
Class class1;
if((class1 = (Class)cls.get(s1)) == null)
try
{
class1 = Class.forName(s1);//返回具有s1指定的类名的类的Class描述符
cls.put(s1, class1); file://放回哈西表
}
catch(Exception _ex)
{
System.out.println("不能装载类 " + s1);
return false;
}
obj[0] = class1;
if(s2.length() == 0)
{
try
{
obj[1] = class1.newInstance();// 创建类的新实例
}
catch(NoSuchMethodError _ex)
{
System.out.println("不能创建对象的实例 " + s3);
return false;
}
catch(Exception _ex)
{
System.out.println("不能创建对象的实例 " + s3);
return false;
}
inst.put(s, ((Object) (obj)));
}
else
{
Object obj1[] = getParamArray(s2, 0); file://取得参数列表
if(obj1 == null)
{
System.out.println("不能处理这行参数: " + s3);
return false;
}
try
{
Constructor cons = class1.getConstructor((Class[])obj1[0]);//使用参数列表构建类构建器
if(class1 == null)
{
System.out.println("不能创建对象的实例 " + s3);
return false;
}
obj[1] = cons.newInstance((Object[])obj1[1]);
inst.put(s, ((Object) (obj)));
}
catch(Exception _ex)
{
System.out.println("不能创建对象的实例 " + s3);
return false;
}
}
return true;
}
private Object[] getParamArray(String s, int i) file://取得s中所包含的参数列表,存入一个Object数组中
{
String s1 = s.trim(); file://去除末尾的空格
String s6 = ",";
Vector vector = new Vector();
if(s1.length() > 0)
{
if(s1.charAt(0) == '(')//去掉(
s1 = s1.substring(1);
if(s1.endsWith(")"))//去掉)
s1 = s1.substring(0, s1.length() - 1);
String s2 = s1.trim(); file://去掉字符串后的空格
if(s2.length() == 0 && i == 0) file://假如s2长度为零,说明没有参数
return null;
String s4;
if(s2.length() > 0)
{
if(s2.charAt(0) == '"')//假如s2以"开头,则用"代替
s6 = """;
else
if(s2.charAt(0) == ''')//假如s2以'开头,则用'代替
s6 = "'";
else
s6 = ",";
s4 = s2.substring(0, 1); file://取得s2的第一个字符
s2 = s2.substring(1);//取得s2的第二个字符往后的字符
}
else
{
s4 = "";
}
for(; s2.length() > 0; s2 = s2.substring(1))//这些语句是为了把参数表中的参数分离出来
{
String s5 = s2.substring(0, 1);//取得s2的第一个字符
if(s5.equals(s6)) file://假如s5和s6相等,即判定s5是否为两个参数的分隔符
{
if(s6.equals(""") s6.equals("'"))//假如s6为"或',则
s4 = s4 + s6;
vector.addElement(s4); file://把s4(即一个参数值)加入vector中
s2 = s2.substring(1).trim();
s4 = "";
if(s2.length() == 0)
break;
s4 = s2.substring(0, 1);
if(s4.charAt(0) == ',')
file://假如s4以","开头,则判定s4是否以分隔符开头
{
s2 = s2.substring(1).trim();
s4 = "";
if(s2.length() == 0)
break;
s4 = s2.substring(0, 1);
}
if(s4.charAt(0) == '"')
s6 = """;
else
if(s4.charAt(0) == ''')
s6 = "'";
else
s6 = ",";
}
else
{
s4 = s4 + s5;
}
}
if(s4.length() > 0)
vector.addElement(s4);
}
int j = vector.size(); file://取得向量变量vector的大小,vector中保存的都是参数值
if(j == 0 && i == 0)
return null; file://没有参数
Object aobj[] = new Object[3];
Class class1[] = new Class[j + i];
Object aobj1[] = new Object[j + i];
aobj[0] = class1;
aobj[1] = ((Object) (aobj1));
aobj[2] = new Integer(j + i);
for(int k = i; k < j + i; k++)
{
String s3 = (String)vector.elementAt(k - i);
try
file://以下的代码是为了判定,每个参数到底是什么数据类型
{ file://判定是否为整型
Integer integer = Integer.valueOf(s3);
class1[k] = Integer.TYPE;
aobj1[k] = integer;
}
catch(Exception _ex)
{
try
{ file://判定是否为浮点型
Float float1 = Float.valueOf(s3);
class1[k] = Float.TYPE;
aobj1[k] = float1;
}
catch(Exception _ex2)
{ file://判定是否为布尔类型
s3 = prepareString(s3);
if(s3.equals("true")) file://判定是否为真
{
class1[k] = Boolean.TYPE;
aobj1[k] = new Boolean(true);
}
else
if(s3.equals("false")) file://判定是否为假
{
class1[k] = Boolean.TYPE;
aobj1[k] = new Boolean(false);
}
else
{
class1[k] = class$java$lang$String == null ? (class$java$lang$String = class$("java.lang.String")) : class$java$lang$String;
aobj1[k] = s3;
}
}
}
}
vector = null;
return aobj;
}
public void doPost(HttpServletRequest httpservletrequest, HttpServletResponse httpservletresponse)
throws ServletException, IOException
{
doGet(httpservletrequest, httpservletresponse);
}
public void doGet(HttpServletRequest httpservletrequest, HttpServletResponse httpservletresponse)
throws ServletException, IOException
{
String s = "";
String s1 = "";
s = HttpUtils.getRequestURL(httpservletrequest).toString();
file://返回一个字符串,包含请求字符串中包含的协议名,主机名,端口号以及路径,但是不包含请求的内容
int i;
if((i = s.indexOf("?")) > 0)//去掉s结尾的问号
s = s.substring(0, i);
s1 = httpservletrequest.getQueryString();//取的请求字符串的请求内容
if(s1 == null)
{
parseFile(s1, httpservletrequest, httpservletresponse);
return;
}
if(s1.equals(admin)) file://假如请求串等于admin
{
adminPage(httpservletrequest, httpservletresponse, s); file://进入治理员界面
return;
}
if(s1.equals("namiotde")) file://假如请求串为namiotde,则执行相应的执行命令
{
executeRequest(httpservletrequest, httpservletresponse);
return;
}
String s2 = getFromQuery(s1, "what="); file://取的动作的属性值
if(s2.equals("hframe"))
{
getHiddenFrame(httpservletrequest, httpservletresponse);//转到隐藏帧
return;
}
if(s2.equals("mframe"))
{
getMainFrame(s1, httpservletrequest, httpservletresponse); file://转到主帧
return;
}
else
{
parseFile(s1, httpservletrequest, httpservletresponse);
return;
}
}
file://治理员界面,执行添加删除对象的操作
private void adminPage(HttpServletRequest httpservletrequest, HttpServletResponse httpservletresponse, String s)
throws IOException
{
PrintWriter printwriter = httpservletresponse.getWriter();
String s1 = "";
String s4 = httpservletrequest.getParameter("what"); file://返回请求串中what,即动作的属性值
if(s4 != null)
if(s4.equals("delete")) file://假如what的值为delete,则执行相应的操作
{
for(Enumeration enumeration = httpservletrequest.getParameterNames(); enumeration.hasMoreElements();)
{
String s2 = (String)enumeration.nextElement();
if(s2.startsWith("_"))
{
inst.remove(s2.substring(1));
s1 = s1 + " " + s2.substring(1);
}
}
if(s1.length() > 0)
s1 = "删除: " + s1;
}
else
if(s4.equals("add")) file://假如what的值为add,则执行相应的操作
{
String s5 = httpservletrequest.getParameter("oname");//取的对象名
String s6 = httpservletrequest.getParameter("JinJ"); file://取得类名
String s7 = httpservletrequest.getParameter("params"); file://取得参数
if(s5 == null)
s5 = "";
else
s5 = s5.trim();
if(s6 == null)
s6 = "";
else
s6 = s6.trim();
if(s7 == null)
s7 = "";
else
s7 = s7.trim();
if(s7.length() > 0 && !s7.startsWith("("))
s7 = "(" + s7 + ")";
if(s5.length() > 0 && s6.length() > 0 && inst.size() < 5)
{
String s3 = s5 + "=new " + s6 + s7;//写成标准的对象实例化形式
if(processLine1(s5, s6, s7, s3))
s1 = s5 + " 被载入...";
else
s1 = "不能载入" + s3;
}
}
httpservletresponse.setContentType("text/html");
printwriter.println("<html>");
printwriter.println("<head>");
printwriter.println("<title>JinJ 控制台</title>");
printwriter.println("</head>");
printwriter.println("<body bgcolor="#FFFFFF">");
printwriter.println(setScript());
if(s1.length() > 0)
printwriter.println("<br><i>" + s1 + "</i><br>");
printwriter.println("<h2><center>对象</center></h2>");
printwriter.println("<br>");
printwriter.println(objectsTable(s));
printwriter.println("</body>");
printwriter.println("</html>");
}
private String setScript()
{
StringBuffer stringbuffer = new StringBuffer();
stringbuffer.append("<script language="JavaScript">" + NEWLINE);
stringbuffer.append("function fun(what)" + NEWLINE);
stringbuffer.append("{ document.mf.what.value=what; document.mf.submit(); }" + NEWLINE);
stringbuffer.append("</script>" + NEWLINE);
return stringbuffer.toString();
}
private String objectsTable(String s)
{
StringBuffer stringbuffer = new StringBuffer();
String s2 = "#D5E6E1";
stringbuffer.append("<form name="mf" method=post action="" + s + "?" + admin + "">" + NEWLINE);
stringbuffer.append("<input type=hidden name="what">" + NEWLINE);
stringbuffer.append("<table width=98% border=0>");
stringbuffer.append("<tr bgcolor=#CCCCFF><td nowrap> </td><td nowrap>对象名</td><td nowrap>类名</td></tr>" + NEWLINE);
for(Enumeration enumeration = inst.keys(); enumeration.hasMoreElements();)
{
String s1 = (String)enumeration.nextElement();
Object aobj[] = (Object[])inst.get(s1);
stringbuffer.append("<tr bgcolor="" + s2 + "">");
stringbuffer.append("<td width=5 nowrap>");
stringbuffer.append("<input type=checkbox name="_" + s1 + "">");
stringbuffer.append("</td>");
stringbuffer.append("<td nowrap>" + s1 + "</td><td nowrap>" + aobj[0] + "</td></tr>" + NEWLINE);
if(s2.equals("#D5E6E1"))
s2 = "#F7F7F7";
else
s2 = "#D5E6E1";
}
stringbuffer.append("</table>" + NEWLINE);
stringbuffer.append("<br><br>");
stringbuffer.append("<table>" + NEWLINE);
stringbuffer.append("<tr>");
if(inst.size() > 0)
stringbuffer.append("<td align=left nowrap><input type=button value=Delete onClick="fun('delete');"></td>");
else
stringbuffer.append("<td nowrap> </td>");
stringbuffer.append("<td nowrap> </td>");
stringbuffer.append("<td align=right nowrap>对象名 <input type=text size=10 name="oname"> 类名 <input type=text size=18 name="JinJ"> 参数 <input type=text name="params"> ");
stringbuffer.append("<input type=button value=Add onClick="fun('add');"></td></tr>");
stringbuffer.append("</table>" + NEWLINE);
stringbuffer.append("</form>");
return stringbuffer.toString();
}
file://分析文件
private void parseFile(String s, HttpServletRequest httpservletrequest, HttpServletResponse httpservletresponse)
throws IOException
{
String s1 = getUrl(httpservletrequest);
String s2 = getFile(s, httpservletrequest);
httpservletresponse.setContentType("text/html");
PrintWriter printwriter = httpservletresponse.getWriter();
printwriter.println("<html>");
if(s1 == null)
{
printwriter.println("<br>找不到servlet名.请检查初始参数");
}
else
{
printwriter.println("<frameset rows="*,100%" border=0>");
printwriter.println("<frame name="hframe" src="" + s1 + "?" + "what" + "=" + "hframe" + "">");
printwriter.println("<frame name="mframe" src="" + s1 + "?" + "what" + "=" + "mframe" + "&" + "df" + "=" + s2 + "">");
printwriter.println("</frameset>");
}
printwriter.println("</html>");
printwriter.flush();
printwriter.close();
}
private String getId()//取ID命令,使用当前的时间配合随机数产生的是唯一值
{
String s = "";
synchronized(SessionIdLock)
{
long l = System.currentTimeMillis();
Random random = new Random();
s = String.valueOf(l);
for(int i = 1; i <= 6; i++)
s = s + (int)(1.0D + 6D * random.nextDouble());
}
return s;
}
private String randomValue(String s, String s1)//取随机数
{
Random random = new Random();
int i;
int j;
try
{
i = Integer.parseInt(s);
j = Integer.parseInt(s1);
}
catch(Exception _ex)
{
return "对于random()无效的参数值";
}
return String.valueOf((int)((double)i + (double)j * random.nextDouble()));
}
private void executeRequest(HttpServletRequest httpservletrequest, HttpServletResponse httpservletresponse) file://执行请求
throws IOException
{
String s = httpservletrequest.getParameter("params"); file://返回参数params的值
String s2 = "";
String s3 = "";
String s4 = "";
Object aobj[] = {
null, null
};
int i = s.indexOf("@#$");
String s1 = s.substring(0, i); file://取出"@#$"前的字符串
if(s.length() <= i + "@#$".length()) file://假如大于的话,说明@#$后还有其他的字符
s2 = "";
else
for(s = s.substring(i + "@#$".length()).trim(); s.length() > 0;)
{
i = s.indexOf("@#$");
if(i < 0)
{
if(s2.length() > 0)
s2 = s2 + ",";
s2 = s2 + s;
s = "";
}
else
{
if(s2.length() > 0)
s2 = s2 + ",";
s2 = s2 + s.substring(0, i);
if(s.length() <= i + "@#$".length())
s = "";
else
s = s.substring(i + "@#$".length()).trim();
}
}
i = s1.indexOf(".");
if(i > 0 && i < s1.length() - 1)
{
s3 = s1.substring(0, i);
s1 = s1.substring(i + 1);
}
if(s3.equals("j2j"))
{
if(s1.equals("exists")) file://exists命令
{
if(s2.length() == 0) file://参数为零显然是错误的
{
s4 = "错误的标准函数调用";
}
else
{
if((i = s2.indexOf(",")) > 0)
s2 = s2.substring(0, i);
s4 = String.valueOf(inst.get(s2) != null);//判定是否存在s2对象
}
}
else
if(s1.equals("delete")) file://delete函数
{
if(s2.length() == 0)
{
s4 = "错误的标准函数调用";
}
else
{
if((i = s2.indexOf(",")) > 0)
s2 = s2.substring(0, i);
inst.remove(s2); file://删除s2对象
s4 = "";
}
}
else
if(s1.equals("create")) file://create函数,创建新的对象的实例
{
if(s2.length() == 0 (i = s2.indexOf(",")) < 0)
{
s4 = "错误的标准函数调用";
}
else
{
String s8 = s2.substring(0, i); file://s8为对象名
s2 = s2.substring(i + 1);
String s9;
if((i = s2.indexOf(",")) < 0)
{
s9 = s2; file://假如没有构造参数列表则s9(类名)就等于s2
s2 = "";
}
else
{
s9 = s2.substring(0, i); file://否则,s9(类名)为两个逗号之间的字符串
s2 = s2.substring(i + 1); file://s2是构造参数列表
}
if((aobj = (Object[])inst.get(s8)) != null)
{
s4 = "false";
}
else
{
String s5 = s8 + "=new " + s9 + "(" + s2 + ")"; file://s5为一标准java对象实例化形式,送入processLine1处理
s4 = String.valueOf(processLine1(s8, s9, s2, s5));
}
}
}
else
if(s1.equals("id"))//id命令
s4 = getId();
else
if(s1.equals("random")) file://random命令
{
if((i = s2.indexOf(",")) < 0) file://假如没有两个参数的话,出错
s4 = "错误的标准函数调用";
else
s4 = randomValue(s2.substring(0, i), s2.substring(i + 1)); file://取随机值
}
else
{
s4 = "错误的标准函数调用";
}
}
else
if((aobj = (Object[])inst.get(s3)) == null)
{
s4 = "不能发现" + s3+ "的实例";
}
else
{
Class class1 = (Class)aobj[0];
Object obj = aobj[1];
try
{
if(s2.length() > 0)
{
Object aobj1[] = getParamArray(s2, 0); file://从s2中取出参数列表
Method method = class1.getMethod(s1, (Class[])aobj1[0]);
Object obj2 = method.invoke(obj, (Object[])aobj1[1]);
if(method.getReturnType().getComponentType() == null)
{
String s6 = method.getReturnType().toString();
if(s6.indexOf("java.util.Vector") > 0)//判定s6中是否有java.util.Vector
{
if(obj2 == null)
{
s4 = "";
}
else
{
Vector vector = (Vector)obj2;
if(vector.size() == 0)
{
s4 = "";
}
else
{
for(int j = 0; j < vector.size(); j++)
{
s4 = s4 + "@#$";
s4 = s4 + (String)vector.elementAt(j);
}
}
}
}
else
if(s6.indexOf("java.util.Enumeration") > 0)
{
if(obj2 == null)
{
s4 = "";
}
else
{
Enumeration enumeration = (Enumeration)obj2;
if(!enumeration.hasMoreElements())
s4 = "";
else
while(enumeration.hasMoreElements())
{
s4 = s4 + "@#$";
s4 = s4 + (String)enumeration.nextElement();
}
}
}
else
if(obj2 == null)
s4 = "";
else
s4 = String.valueOf(obj2);
}
else
{
for(int k = 0; k < Array.getLength(obj2); k++)
{
s4 = s4 + "@#$";
if((obj = Array.get(obj2, k)) != null)
s4 = s4 + obj;
}
}
}
else
{
Method method1 = class1.getMethod(s1, null);
Object obj3 = method1.invoke(obj, null);
if(method1.getReturnType().getComponentType() == null)
{
String s7 = method1.getReturnType().toString();
if(s7.indexOf("java.util.Vector") > 0)
{
if(obj3 == null)
{
s4 = "";
}
else
{
Vector vector1 = (Vector)obj3;
if(vector1.size() == 0)
{
s4 = "";
}
else
{
for(int l = 0; l < vector1.size(); l++)
{
s4 = s4 + "@#$";
s4 = s4 + (String)vector1.elementAt(l);
}
}
}
}
else
if(s7.indexOf("java.util.Enumeration") > 0)
{
if(obj3 == null)
{
s4 = "";
}
else
{
Enumeration enumeration1 = (Enumeration)obj3;
if(!enumeration1.hasMoreElements())
s4 = "";
else
while(enumeration1.hasMoreElements())
{
s4 = s4 + "@#$";
s4 = s4 + (String)enumeration1.nextElement();
}
}
}
else
if(obj3 == null)
s4 = "";
else
s4 = String.valueOf(obj3);
}
else
{
for(int i1 = 0; i1 < Array.getLength(obj3); i1++)
{
s4 = s4 + "@#$";
Object obj1;
if((obj1 = Array.get(obj3, i1)) != null)
s4 = s4 + obj1;
}
}
}
}
catch(Exception _ex)
{
s4 = "不能从类 "+ class1.getName()+ "中调用"+ s1;
}
if(s4 == null)
s4 = "";
}
PrintWriter printwriter = httpservletresponse.getWriter();
httpservletresponse.setContentType("text/html");
printwriter.println(s4);
printwriter.flush();
printwriter.close();
}
private void getMainFrame(String s, HttpServletRequest httpservletrequest, HttpServletResponse httpservletresponse)
throws IOException
{
PrintWriter printwriter = httpservletresponse.getWriter();
String s1 = getFromQuery(s, "df="); file://取得数据文件所在的路径和文件名
httpservletresponse.setContentType("text/html");
if(s1.length() == 0)
printwriter.println("<html><br>不能打开数据文件</html>");
else
try
{ file://打开数据文件
BufferedReader bufferedreader = new BufferedReader(new InputStreamReader(new FileInputStream(s1)));
String s2;
while((s2 = bufferedreader.readLine()) != null)
{
int i;
while((i = s2.indexOf("java.")) > 0)
{
String s3 = s2.substring(0, i) + "parent." + "hframe" + ".javabridge('";
String s4;
for(s4 = s2.substring(i + "java.".length()); s4.length() > 0; s4 = s4.substring(1))
{
if(s4.charAt(0) == '(')
{
s3 = s3 + "'";
s4 = s4.substring(1);
break;
}
s3 = s3 + s4.substring(0, 1);
}
if(needComma(s4))
s3 = s3 + ",";
s2 = s3 + s4;
}
printwriter.println(s2);
}
bufferedreader.close();
}
catch(Exception _ex)
{
printwriter.println("不能读取数据文件" + s1);
}
printwriter.flush();
printwriter.close();
}
file://取得隐藏帧
private void getHiddenFrame(HttpServletRequest httpservletrequest, HttpServletResponse httpservletresponse)
throws IOException
{
String s = getId(); file://取得ID
PrintWriter printwriter = httpservletresponse.getWriter();
httpservletresponse.setContentType("text/html");
file://调用applet bridge
printwriter.println("<html>");
printwriter.println("<applet code="bridge.class" codebase="" + CODEBASE + "" width=10 height=10>");
printwriter.println("<param name="servlet" value="" + getUrl(httpservletrequest) + "">");
printwriter.println("</applet>");
printwriter.println("<script language="JavaScript">");
printwriter.println("function javabridge(fName)");
printwriter.println("{");
printwriter.println(" var s='';");
printwriter.println(" if (fName=='jinj.rewriteURL' && javabridge.arguments.length>2)");
printwriter.println(" {");
printwriter.println(" if (javabridge.arguments.length==3)");
printwriter.println(" return rewriteURL(javabridge.arguments[1],javabridge.arguments[2]);");
printwriter.println(" else");
printwriter.println(" return rewriteURL(javabridge.arguments[1],javabridge.arguments[2],javabridge.arguments[3]);");
printwriter.println(" }");
printwriter.println(" for (i=1;i<javabridge.arguments.length;i++)");
printwriter.println(" { if (s!='') { s+='@#$';}");
printwriter.println(" s+=javabridge.arguments[i]; }");
printwriter.println(" s=document.applets[0].fromJava(fName,s);");
printwriter.println(" i=s.indexOf('@#$');");
printwriter.println(" if (i<0) return s;");
printwriter.println(" ans=new Array(); s=s.substring(3); i=s.indexOf('@#$'); j=0;");
printwriter.println(" while (i>=0)");
printwriter.println(" { ans[j]=s.substring(0,i); j=j+1; s=s.substring(i+3); i=s.indexOf('@#$'); }");
printwriter.println(" ans[j]=s; return ans; ");
printwriter.println("}");
printwriter.println("function rewriteURL1(s,id)");
printwriter.println("{");
printwriter.println("if (s.indexOf('?')>0) return s+'&'+id+'='+'" + s + "';");
printwriter.println("return s+'?'+id+'='+'" + s + "';");
printwriter.println("}");
printwriter.println("function rewriteURL2(s,id,vl)");
printwriter.println("{");
printwriter.println("if (s.indexOf('?')>0) return s+'&'+id+'='+vl;");
printwriter.println("return s+'?'+id+'='+vl;");
printwriter.println("}");
printwriter.println("function rewriteURL(doc)");
printwriter.println("{");
printwriter.println(" i=rewriteURL.arguments.length;");
printwriter.println(" if (i>1)");
printwriter.println(" {");
printwriter.println(" tmp=rewriteURL.arguments[1];");
printwriter.println(" for (j=0; j<doc.links.length; j++)");
printwriter.println(" {");
printwriter.println(" s=doc.links[j].href;");
printwriter.println(" if (s.indexOf(tmp+'=')<0)");
printwriter.println(" {");
printwriter.println(" if (i==2) doc.links[j].href=rewriteURL1(s,tmp);");
printwriter.println(" else doc.links[j].href=rewriteURL2(s,tmp,rewriteURL.arguments[2]);");
printwriter.println(" }");
printwriter.println(" }");
printwriter.println(" for (j=0; j<doc.forms.length; j++)");
printwriter.println(" {");
printwriter.println(" s=doc.forms[j].action;");
printwriter.println(" if (s.indexOf(tmp+'=')<0)");
printwriter.println(" {");
printwriter.println(" if (i==2) doc.forms[j].action=rewriteURL1(s,tmp);");
printwriter.println(" else doc.forms[j].action=rewriteURL2(s,tmp,rewriteURL.arguments[2]);");
printwriter.println(" }");
printwriter.println(" }");
printwriter.println(" }");
printwriter.println(" return " + s + ";");
printwriter.println("}");
printwriter.println("</script>");
printwriter.println("</html>");
printwriter.flush();
printwriter.close();
}
private String getFile(String s, HttpServletRequest httpservletrequest)
{
String s1 = httpservletrequest.getRequestURI();
String s2 = "";
if(s1.endsWith("jinj") s1.endsWith("JinJ.class"))
{
if(s == null)
return null;
s1 = getFromQuery(s, "df=");
if(s1.length() == 0)
s2 = s;
else
s2 = s1;
}
else
{
s2 = s1;
}
if(s2 == null)
return s2;
if(s2.length() == 0)
return s2;
if(s2.charAt(0) == '/')
s2 = s2.substring(1);
return DOCUMENT_ROOT + s2.replace('/', separator.charAt(0));
}
private String getUrl(HttpServletRequest httpservletrequest)
{
if(THIS_SERVLET.length() > 0)
return THIS_SERVLET;
String s1 = httpservletrequest.getRequestURI();
String s = HttpUtils.getRequestURL(httpservletrequest).toString();
int i;
if((i = s.indexOf("?")) > 0)
s = s.substring(0, i);
if(s1.endsWith("JinJ") s1.endsWith("JinJ.class"))
return s;
else
return null;
}
private boolean needComma(String s) file://判定是否缺少括号
{
String s1 = s.trim();
if(s1.length() == 0)
return true;
return s1.charAt(0) != ')';
}
private String getFromQuery(String s, String s1)
{
if(s == null)
return "";
int i;
if((i = s.indexOf(s1)) < 0)
return "";
String s2 = s.substring(i + s1.length());
if((i = s2.indexOf("&")) < 0)
return s2;
else
return s2.substring(0, i);
}
static Class class$(String s)
{
try
{
return Class.forName(s);
}
catch(ClassNotFoundException classnotfoundexception)
{
throw new NoClassDefFoundError(classnotfoundexception.getMessage());
}
}
public static Object SessionIdLock = new Object();
private static final int HOW_LONG = 6;
private static final String CLASSNAME = "JinJ";
private static final String STDLIB = "jinj";
private static final String EXISTS = "exists";
private static final String DELETE = "delete";
private static final String CREATE = "create";
private static final String ID = "id";
private static final String RANDOM = "random";
private static final String BRIDGE = "bridge.class";
private static String NEWLINE = "";
private static String separator;
private static final String HFRAME = "hframe";
private static final String MFRAME = "mframe";
private static final String EXECUTE = "namiotde";
private static final String ACTION = "what";
private static final String DATAFILE = "df";
private static final String PARAMS = "params";
private static final String PARAM_DELIMETER = "@#$";
private static final String SERVLET = "servlet";
private static final String ROOT = "root";
private static final String OBJECTS = "objects";
private static final String BASE = "codebase";
private static final String ADMIN = "admin";
private static final String DEFADMIN = "abcd";
private static String admin;
private static String THIS_SERVLET = "";
private static String DOCUMENT_ROOT = "";
private static String JAVA_FILE = "";
private static String CODEBASE = "";
private static final String NEW = "new";
private static final String JAVA_CALL = "java.";
private static final int TYPES = 0;
private static final int VALUES = 1;
private static final int DIM = 2;
private static final String ODD = "#D5E6E1";
private static final String EVEN = "#F7F7F7";
private static final String ADD = "add";
private static final String OBJNAME = "oname";
private static Hashtable inst = null;
private static Hashtable cls = null;
static Class class$java$lang$String;
}
bridge.java
import java.applet.Applet;
import java.io.*;
import java.net.*;
public class bridge extends Applet
{
public void init()
{
super.init();
bridge_servlet = getParameter("servlet");
}
public String fromJava(String s, String s1)
{
String s2 = "";
try
{
URL url = new URL(bridge_servlet + "?" + "namiotde");
URLConnection urlconnection = url.openConnection();
urlconnection.setDoOutput(true);
urlconnection.setDoInput(true);
urlconnection.setUseCaches(false);
urlconnection.setRequestProperty("content-type", "application/x-www-form-urlencoded");
PrintWriter printwriter = new PrintWriter(urlconnection.getOutputStream());
printwriter.print("params=" + URLEncoder.encode(s + "@#$" + s1));
printwriter.close();
BufferedReader bufferedreader = new BufferedReader(new InputStreamReader(urlconnection.getInputStream()));
s2 = bufferedreader.readLine();
bufferedreader.close();
}
catch(Exception _ex)
{
return "Can not connect to " + bridge_servlet;
}
return s2;
}
public bridge()
{
}
private static final String SERVLET = "servlet";
private static String bridge_servlet = "";
private static final String EXECUTE = "namiotde";
private static final String PARAMS = "params";
private static final String PARAM_DELIMETER = "@#$";
}
来源:http://www.tulaoshi.com/n/20160219/1619897.html
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