Java
-
JSP PageContext. Release() method: release related resources
release() Example <% pageContext.release(); %> -
Detailed explanation of Java one-dimensional array: Java creates one-dimensional array, initializes one-dimensional array, and obtains single / all elements
Create a one-dimensional array 数据类型数组名[]; //声明数组 数据类型[]数组名; //声明数组 int[] score; /…… -
JSP application. Getresourcepaths() method: returns all files in the specified directory
getResourcePaths(String path) Example <% Set set = application.getResourcePaths("/"); //返回装载指定路径列表…… -
JSP Request. Getheadersnames() method: returns the names of all request headers
getHeaderNames() Example <% Enumeration cts = request.getHeaderNames(); while(cts.hasMoreElements()){ …… -
JSP Request. Getintheader () method: get the corresponding header information in the client request
getIntHeader(String name) Example <% out.println(request.getIntHeader("Expires")); %> -
Java List. Get () method: get the element at the specified position in the list
get(int index) Typical application public static void main(String[] args){ List<String>list = new ArrayLi…… -
JSP application. Getattributenames() method: get all attribute names
getAttributeNames() Example <% Enumeration names = application.getAttributeNames(); while(names.hasMoreElem…… -
JSP Response. Getoutputstream () method: get the output stream of the JSP response object
getOutputStream() Example <% ServletOutputStream os = response.getOutputStream(); os.write("<b>Java编…… -
JSP Response. Addinthead() method: add the int attribute of the corresponding name
addIntHeader(String name,int value) Example <% response.addIntHeader("Expires",10); %> -
Role of Java currentthread() method
Example 1 public class Run1 { public static void main(String[] args) { //调用currentThread()方法…… -
JSP PageContext. Handlepageexception() method: throw an exception
Grammar 1 handlePageException(Exception e) Example <%@page language="java" pageEncoding="GBK" errorPage="error.js…… -
JSP page instruction: page instruction
<%@page [language="java"] [contentType="mimeType;charset=CHARSET"] [import="{package.class|pageage.*},……"] [extends…… -
The role of the Java getid () method
package ch14; public class Test15 { public static void main(String[] args) { Thread runThread=T…… -
Basic knowledge of Java network programming
Network classification Network programming model Client / Server Mode Browser / Server Mode Network protocol IP protoc…… -
JSP Request. Getmethod () method: get the method that the client transmits data to the server
getmethod() Example <% String mName = request.getmethod(); out.println("表单提交请求使用的方法是:"+mName); …… -
JSP Response. Addcookie() method: add cookie object
addCookie(Cookie cookie) Example <% Cookie cookie = new Cookie("user","lzw"); response.addCookie(cookie); …… -
Java connection string
Using join operators Example 1 public static void main(String[] args) { int[] no=new int[]{501,101,204,102,334…… -
JSP PageContext. Getrequest () method: get the current request object
getRequest() <% HttpServletRequest req = (HttpServletRequest)pageContext.getRequest(); String name = req.ge…… -
JSP Request. Isrequestedsessionidvalid() method: Returns whether the session is valid
isRequestedSessionIdValid() Example <% out.println("Session是否有效"+request.isRequestedSessionIdValid()); %&…… -
Jsp: forward: request forwarding tag
The < jsp: param > sub tag is used to pass parameters to the dynamic target file. The key codes are as follows: …… -
Java Statement. Getgeneratedkeys() method: get the automatically generated key
getGeneratedKeys() Example Connection conn = …… //省略部分代码 Statement stmt = conn.createStatement(); //获取Sta…… -
Java lastindexof() method: returns the index position of the last occurrence
Grammar 1 lastIndexOf(int ch) Example String strCom = "abcdefg gfdecba"; int index = strCom.lastIndexOf("a"); Gramm…… -
JSP config. The getinitparameter () method gets the value of the initial parameter
getInitParameter(String name) Example <% String name = config.getInitParameter("fork"); out.println("parame…… -
Java Map. Keyset() method: get all the key names of the map set
keySet() Typical application public static void main(String[] args){ Map map = new HashMap(); //定义Map集合 …… -
Java Map. Isempty() method: judge whether the map collection object contains content
isEmpty() Example public static void main(String[] args){ System.out.println("创建Map集合对象"); Map map =…… -
JSP Request. Getremoteaddr() method: get the IP address of the requesting client
getRemoteAddr() Example <% String p = request.getRemoteAddr(); out.println("客户端的IP地址为:"+p); %> -
Comparison of Java strings (equals(), equalsignorecase(), compareto())
Equals() method 字符串1.equals(字符串2); String str1="abc"; String str2=new String("abc"); String str3="ABC"; S…… -
What is JSP? What are the advantages of JSP?
1) Precompiled 2) Separation of business codes 3) Component reuse 4) Cross platform -
JSP config. Getinitparameter() method: get the value of the initial parameter
getInitParameter(String name) Example <% String name = config.getInitParameter("fork"); out.println("parame…… -
JSP PageContext. Forward() method: forward page
forward(String relativeUrlPath) Example <% pageContext.forward("count.jsp"); %> Typical application &l…… -
Detailed explanation of Java two-dimensional array: Declaration and initialization of two-dimensional array, and obtaining the value of two-dimensional array
Create a 2D array type array[][]; type[][] array; int[][] age; char[][] sex; Initialize 2D array array=new typ……