一、已知有一个建好的jsp 项目,我如何导入到 MyEclipse 中? 右击 PackageExplorer--import--General--ExistingProjectsintoWorkspace 。 该项目中 MySQL 端口: 3306 密码: wjdTomcat : 8080 二、为何要同时使用 Dreamweaver 与 MyEclipse ? 同时使用 D
一、已知有一个建好的jsp项目,我如何导入到MyEclipse中?
右击Package Explorer-->import-->General--> Existing Projects into Workspace。
该项目中MySQL端口:3306 密码:wjd Tomcat:8080
二、为何要同时使用Dreamweaver与MyEclipse?
同时使用Dreamweaver与MyEclipse是为了方便网站建设,Dreamweaver用来布局页面,而MyEclipse主要负责后台与前台中jsp的编码。在Dreamweaver中建立站点,把站点地址设置成MyEclipse的工程目录。
当在Dreamweaver中修改页面内容后,在MyEclipse中刷新整个项目;当在MyEclipse中修改页面内容后,在Dreamweaver中会出现“是否加载外部修改”,选择“是”,则保证了两边编辑同步。
三、已知一个sql文件,如何导入MySQL中?
利用Navicat软件实现MySQL的界面化。打开Navicat新建连接,然后新建一个数据库,然后点击工具-->console-->把sql类型文件中的内容复制到console编辑栏目中,点击回车,sql导入成功。
四、中文乱码问题
1、在MyEclipse中设置JSP页面编码步骤如下:
依次点击windows-> Preferences-> MyEclipse-> Files&Editors-> JSP-> encoding:设置为ISO10646/Unicode(UTF-8)。
2、在JSP页面中:
字符编码" pageEncoding="字符编码"%>
字符编码">
保存JSP文件时的编码选项必须与jsp页面中的pageEncoding属性中配置的编码一致(或者在没有pageEncoding属性时与 contentType属性中配置的编码一致,两者的优先级是:pageEncoding>contentType),才不会出现乱码。
3、MySQL中也需要设置编码为utf-8。
4、提交表单时在doPost函数中添加request.setCharacterParameter("utf-8"); 语句。
五、比较alert("msg")、 confirm("msg")、 prompt("msg")
警告框:window.alert(str)或alert(str)
确认框:answer = window.confirm(str)或answer = confirm(str)
提示框:returnStr = window.prompt(targetQuestion,defaultString)
或prompt(targetQuestion,defaultString)
alert()和confirm()的最大区别是alert()没有返回值,confirm()的返回值有两种,一个是return false,一个是return true。当confirm()的对话框跳出时,点击确认,返回值就是true,点击取消,返回的是false。
六、新建JSP页面
新建JSP页面时,选择JSP(Basic templates)。
jsp页面的静态部分,如HTML、CSS标记等,用来完成页面布局和显示样式;jsp页面的动态部分,如脚本程序、jsp
JSP声明举例如下:
synchronized void count() {number++;}
%> //此段代码声明了一个变量number和一个方法count,它们可以在整个jsp页面的任何位置上使用
你是第个访问本站的客户
JSP内建对象有:
1、out:传送信息到客户端的浏览器
eg1:out.println("Hello,JSP
");
eg2:out.println(i)
2、request:包装客户端的请求信息;
3、response:响应客户端的请求;
4、session:客户端请求的一次会话。会话从客户端连接到服务器开始,直到与服务器断开连接为止,期间都可以访问session对象的属性和方法。
七、request对象、response对象
request对象 : 客户端的请求信息被封装在request对象中,通过它才能了解到客户的需求,然后做出响应。它是HttpServletRequest类的实例。
response对象 : response对象包含了响应客户请求的有关信息,但在JSP中很少直接用到它。它是HttpServletResponse类的实例。
八、比较page、request、session、application的使用范围
在一个页面范围内:page
在一次服务器请求范围内:request
在一次会话范围内:session
在一个应用服务器范围内:application
document是js(
${...}取到的值是request范围内的值,跟request.getAttribute();效果一样。
之所以能取到值,是因为上面javascript中有定义,其实是存在page范围内的。
九、在JSP环境中配置使用FCKeditor
使用在线编辑器必不可少下述语句:
....
FCKeditor oFCKeditor;
oFCKeditor = new FCKeditor(request,"EditorDefault");
oFCKeditor.setBasePath(request,getContextPath()+"/fckeditor/");
oFCKeditor .setVaule(" ");
out.println(oFCKeditor .create());
%>
十、MVC模式
当引入servlet后,由servlet完成控制的功能,同时jsp单纯地完成页面展示功能,这是MVC模式(Model-View-Controller:模型-视图-控制器)。
采用jsp+javaBean+servlet模式设计:
1、一个index.jsp页面。例如用于显示留言簿内容,有一个表单用于提交留言簿内容;
2、一个servlet文件Operate.java。该文件接收表单提交的数据,一般进行三种处理:返回index.jsp所有留言信息;删除留言信息;插入留言信息。
3、一个封装了数据库操作的类DBOperate.java。该类的设计采用了singleton设计模式。
十一、Servlet配置
servlet/jsp Mapping URL : /servlet/add_servlet
File Path of web.xml : /项目名称/WebRoot/WEB-INF
十二、图片上传
图片上传要实现的是:将图片上传到服务器保存到某个文件夹中,将图片名称放到数据库中,图片名称一般根据当前时间来重命名。详情见***。
十三、JSP连接MySQL
DriverManager是管理JDBC驱动程序的接口,它通过getConnection方法获得Connection对象引用。Connection con = DriverManager.getConnection();
Statement是向数据库提交SQL语句并返回相应结果的工具。
ResultSet executeQuery(String sql) throws SQLException
Int executeUpdate(String sql) 返回发生改变的记录条数
Boolean execute(String sql) 判断是否执行成功
PreparedStatement接口继承Statement接口,当一条SQL语句需要稍加变化而反复执行时,通常采用PreparedStatement。
十四、翻页功能
十五、error:Interger与int的转化
项目最后遇到的问题是Interger与int的转化,解决办法就是利用强制转换。
int count = Interger.valueof().intValue();

Stored procedures are precompiled SQL statements in MySQL for improving performance and simplifying complex operations. 1. Improve performance: After the first compilation, subsequent calls do not need to be recompiled. 2. Improve security: Restrict data table access through permission control. 3. Simplify complex operations: combine multiple SQL statements to simplify application layer logic.

The working principle of MySQL query cache is to store the results of SELECT query, and when the same query is executed again, the cached results are directly returned. 1) Query cache improves database reading performance and finds cached results through hash values. 2) Simple configuration, set query_cache_type and query_cache_size in MySQL configuration file. 3) Use the SQL_NO_CACHE keyword to disable the cache of specific queries. 4) In high-frequency update environments, query cache may cause performance bottlenecks and needs to be optimized for use through monitoring and adjustment of parameters.

The reasons why MySQL is widely used in various projects include: 1. High performance and scalability, supporting multiple storage engines; 2. Easy to use and maintain, simple configuration and rich tools; 3. Rich ecosystem, attracting a large number of community and third-party tool support; 4. Cross-platform support, suitable for multiple operating systems.

The steps for upgrading MySQL database include: 1. Backup the database, 2. Stop the current MySQL service, 3. Install the new version of MySQL, 4. Start the new version of MySQL service, 5. Recover the database. Compatibility issues are required during the upgrade process, and advanced tools such as PerconaToolkit can be used for testing and optimization.

MySQL backup policies include logical backup, physical backup, incremental backup, replication-based backup, and cloud backup. 1. Logical backup uses mysqldump to export database structure and data, which is suitable for small databases and version migrations. 2. Physical backups are fast and comprehensive by copying data files, but require database consistency. 3. Incremental backup uses binary logging to record changes, which is suitable for large databases. 4. Replication-based backup reduces the impact on the production system by backing up from the server. 5. Cloud backups such as AmazonRDS provide automation solutions, but costs and control need to be considered. When selecting a policy, database size, downtime tolerance, recovery time, and recovery point goals should be considered.

MySQLclusteringenhancesdatabaserobustnessandscalabilitybydistributingdataacrossmultiplenodes.ItusestheNDBenginefordatareplicationandfaulttolerance,ensuringhighavailability.Setupinvolvesconfiguringmanagement,data,andSQLnodes,withcarefulmonitoringandpe

Optimizing database schema design in MySQL can improve performance through the following steps: 1. Index optimization: Create indexes on common query columns, balancing the overhead of query and inserting updates. 2. Table structure optimization: Reduce data redundancy through normalization or anti-normalization and improve access efficiency. 3. Data type selection: Use appropriate data types, such as INT instead of VARCHAR, to reduce storage space. 4. Partitioning and sub-table: For large data volumes, use partitioning and sub-table to disperse data to improve query and maintenance efficiency.

TooptimizeMySQLperformance,followthesesteps:1)Implementproperindexingtospeedupqueries,2)UseEXPLAINtoanalyzeandoptimizequeryperformance,3)Adjustserverconfigurationsettingslikeinnodb_buffer_pool_sizeandmax_connections,4)Usepartitioningforlargetablestoi


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