普通 Javaweb项目模板的搭建

1. 创建一个普通的 maven 项目

1.1、第一步创建一个普通的 maven 项目

1.2、给 maven 项目注入web支持

现在就是一个web项目了。

2. 配置 Tomcat 服务器

现在就配置好 Tomcat 服务器了！

3. 先测试一下该空项目

如果能够正常访问到页面，则服务器配置没有什么问题；否则，则出现问题。那就得另行解决了。。。。

4. 注入 maven 依赖

web项目需要的jar包：jsp，servlet，mysql驱动，jdbc，jstl，standard .....

  <!-- servlet依赖 -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>3.1.0</version>
      <scope>provided</scope>
    </dependency>

    <!-- JSP依赖 -->
    <dependency>
      <groupId>javax.servlet.jsp</groupId>
      <artifactId>javax.servlet.jsp-api</artifactId>
      <version>2.3.1</version>
      <scope>provided</scope>
    </dependency>

    <!--JSTL表达式依赖-->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>jstl</artifactId>
      <version>1.2</version>
    </dependency>

    <!--standard标签库-->
    <dependency>
      <groupId>taglibs</groupId>
      <artifactId>standard</artifactId>
      <version>1.1.2</version>
    </dependency>

    <!--jdbc -->
    <dependency>
      <groupId>org.clojure</groupId>
      <artifactId>java.jdbc</artifactId>
      <version>0.7.11</version>
    </dependency>

    <!--junit-->
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.12</version>
    </dependency>

    <!--连接mysql数据库依赖-->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.47</version>
    </dependency>

    <!--fastjson依赖-处理json字符串-->
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>fastjson</artifactId>
      <version>1.2.62</version>
    </dependency>

5. 创建项目的包结构

提前建好包，结构清晰，逻辑分明，方便代码的编写。。。。。

6. 编写基础公共类

1. 数据库配置文件（db.properties）

#加载驱动
driver=com.mysql.jdbc.Driver
#加载数据库
#dbname是要连接的数据库名称
url=jdbc:mysql://localhost:3306/dbname?useUnicode=true&characterEncoding=utf-8
#用户名
user=root
#密码
password=123456

2. 编写数据库的公共类

public class DBUtil {
    //静态代码块,在类加载的时候执行
    static{
        init();
    }

    private static String driver;
    private static String url;
    private static String user;
    private static String password;

    //初始化连接参数,从配置文件里获得
    public static void init(){
        Properties params=new Properties();
        String configFile = "db.properties";
        InputStream is= DBUtil.class.getClassLoader().getResourceAsStream(configFile);
        try {
            params.load(is);
        } catch (IOException e) {
            e.printStackTrace();
        }
        driver=params.getProperty("driver");
        url=params.getProperty("url");
        user=params.getProperty("user");
        password=params.getProperty("password");
    }

    /*
    * 获得数据库连接
    * */
    public static Connection getConnection(){
        Connection connection = null;
        try {
            Class.forName(driver);
            connection = DriverManager.getConnection(url, user, password);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return connection;
    }
    /*
    * 查询操作
    * params 是prepareStatement所执行sql语句中 占位符 ？ 的值
    * */
    public static ResultSet execute(Connection connection, PreparedStatement pstm, ResultSet rs,
                                    String sql, Object[] params) throws Exception{
        pstm = connection.prepareStatement(sql);
        for(int i = 0; i < params.length; i++){
            pstm.setObject(i+1, params[i]);
        }
        rs = pstm.executeQuery();
        return rs;
    }
    
    /*
    * 更新操作
    * */
    public static int execute(Connection connection,PreparedStatement pstm,
                              String sql,Object[] params) throws Exception{
        int updateRows = 0;
        pstm = connection.prepareStatement(sql);
        for(int i = 0; i < params.length; i++){
            pstm.setObject(i+1, params[i]);
        }
        updateRows = pstm.executeUpdate();
        return updateRows;
    }
    
    /*
    * 资源回收
    * */
    public static boolean closeResource(Connection connection,PreparedStatement pstm,ResultSet rs){
        boolean flag = true;
        if(rs != null){
            try {
                rs.close();
                rs = null;//GC回收
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
                flag = false;
            }
        }
        if(pstm != null){
            try {
                pstm.close();
                pstm = null;//GC回收
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
                flag = false;
            }
        }
        if(connection != null){
            try {
                connection.close();
                connection = null;//GC回收
            } catch (SQLException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
                flag = false;
            }
        }
        return flag;
    }

3. 编写字符编码过滤器

public class CharacterEncoding implements Filter {

	@Override
	public void init(FilterConfig filterConfig) throws ServletException {
		// TODO Auto-generated method stub

	}

	@Override
	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain chain) throws IOException, ServletException {
		// TODO Auto-generated method stub
		request.setCharacterEncoding("UTF-8");
		response.setCharacterEncoding("UTF-8");
		chain.doFilter(request, response);
	}

	@Override
	public void destroy() {
		// TODO Auto-generated method stub

	}

记得web.xml文件中注册 filter ！

  <filter>
  	<filter-name>CharacterEncoding</filter-name>
  	<filter-class>com.why.filter.CharacterEncoding</filter-class>
  </filter>
  <filter-mapping>
  	<filter-name>CharacterEncoding</filter-name>
  	<url-pattern>/*</url-pattern>
  </filter-mapping>

至此web项目的模板就已经构建的差不多了.....

原文：https://www.cnblogs.com/whyboy/p/14525351.html