JAVA默寫標(biāo)準(zhǔn)文檔.doc

Java 默寫標(biāo)準(zhǔn)Java默寫標(biāo)準(zhǔn)（1.0）1 Java語(yǔ)法(5)繼承extends接口Interface implements抽象abstract靜態(tài)static調(diào)用2 基礎(chǔ)數(shù)據(jù)類型(8)booleancharbyteshort intlongfloatdouble3 數(shù)組(2)1. int userAge=1，2，3，4，5;int userAge =new int2;userAge 0=5;userAge 1=1;2. int allPge=2，3，1，5，3，4; String cityArray = new String 2 3;cityArray 00 = “上海”;cityArray 01 = “無錫”;4 訪問指示符(4) 公有public所有的類都可以訪問友好無前綴在同一個(gè)包內(nèi)可以訪問受到保護(hù)的protected必須為繼承類可訪問私有的private只有本類訪問5 Java類構(gòu)成package com.thunis.teach.case;public class HelloWorld public HelloWorld() 6 異常處理try/代碼塊catch(違例類型e)/此違例類型的控制代碼7 JAVA常用類(2)7.1 String（8）length()charAt(intindex)equals(ObjectanObject) indexOf(Stringstr)substring(intbeginIndex, intendIndex) trim()刪除字符串首部和尾部的空格。toCharArray()：將字符串對(duì)象中的字符轉(zhuǎn)換為一個(gè)字符數(shù)組toLowerCase()toUpperCase() 7.2 StringBuffer實(shí)例化append8 Servlet(5)package com.unissoft.teach.xia;import javax.servlet.ServletException;import javax.servlet.RequestDispatcher;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException;public class AddNumberServlet extends HttpServlet public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException /設(shè)置本頁(yè)字符集為GB2312，以便識(shí)別漢字 request.setCharacterEncoding(GB2312); /從提交頁(yè)面得到text的startnumber的值，并轉(zhuǎn)化成int類型 String addString=request.getParameter(addnumber); /把startnumber放進(jìn)request容器里面 request.setAttribute(addString,addString); /從本頁(yè)面跳轉(zhuǎn)到primenout.jsp頁(yè)面 RequestDispatcher rd=getServletContext().getRequestDispatcher(/addout.jsp); rd.forward(request, response); 9 JSP1. 指令% page import=“java.util.*” % % include file=“relative url” %2.jsp:useBean動(dòng)作 10 Cookie設(shè)置創(chuàng)建Cookie cookieArr = new Cookie(String, Object);加入應(yīng)答response.addCookie(cookie) ;從客戶端讀入Cookie cookies = request.getCookies();cookiesi.getName()；cookiesi.getValue();11 Session創(chuàng)建HttpSession session = request.getSession(true); 賦值session.setAttribute(String,Object)獲取.getAttribute()12 JDBC的功能/確定數(shù)據(jù)庫(kù)連接的類Class.forName(sun.jdbc.odbc.JdbcOdbcDriver);/連接數(shù)據(jù)庫(kù)Connection =DriverManager.getConnection(jdbc:odbc:dateheadstream,);/提交SQL語(yǔ)句Statement st=con.createStatement();/定義sql語(yǔ)句String sqlValue= ;/有返回ResultSet rs=st.executeQuery(sqlValue);13 多態(tài)中注意的問題多態(tài)由句柄的不同進(jìn)行區(qū)分多態(tài)不能通過返回值區(qū)分動(dòng)態(tài)聯(lián)編優(yōu)先選擇最適合的類，逐步向上14 this與superthis代表本類，用于引用本類中的構(gòu)造器以及非靜態(tài)方法和屬性super代