JSF - JDBC Integration

在本文中，我們將演示如何使用JDBC在JSF中集成資料庫。

下面是運行此示例的資料庫要求。

S.No	Software & Description
1	PostgreSQL 9.1 開源輕量級資料庫
2	PostgreSQL JDBC4 Driver PostgreSQL 9.1和JDK 1.5或更高版本的JDBC驅動程序

將PostgreSQL JDBC4驅動程序jar放在tomcat web伺服器的lib目錄中。

Database SQL Commands

create user user1;
create database testdb with owner = user1;

CREATE TABLE IF NOT EXISTS authors (
    id int PRIMARY KEY, 
    name VARCHAR(25)
);

INSERT INTO authors(id, name) VALUES(1, 'Rob Bal');
INSERT INTO authors(id, name) VALUES(2, 'John Carter');
INSERT INTO authors(id, name) VALUES(3, 'Chris London');
INSERT INTO authors(id, name) VALUES(4, 'Truman De Bal');
INSERT INTO authors(id, name) VALUES(5, 'Emile Capote');
INSERT INTO authors(id, name) VALUES(7, 'Breech Jabber');
INSERT INTO authors(id, name) VALUES(8, 'Bob Carter');
INSERT INTO authors(id, name) VALUES(9, 'Nelson Mand');
INSERT INTO authors(id, name) VALUES(10, 'Tennant Mark');

alter user user1 with password 'user1';

grant all on authors to user1;

Example Application

讓我們創建一個測試JSF應用程式來測試JDBC集成。

Step	Description
1	Create a project with a name helloworld under a package com.tutorialspoint.test as explained in the JSF - First Application chapter.
2	Create resources folder under src → main folder.
3	Create css folder under src → main → resources folder.
4	Create styles.css file under src → main → resources → css folder.
5	Modify styles.css file as explained below.
6	Modify pom.xml as explained below.
7	Create Author.java under package com.tutorialspoint.test as explained below.
8	Create UserData.java under package com.tutorialspoint.test as explained below.
9	Modify home.xhtml as explained below. Keep the rest of the files unchanged.
10	Compile and run the application to make sure the business logic is working as per the requirements.
11	Finally, build the application in the form of war file and deploy it in Apache Tomcat Webserver.
12	Launch your web application using appropriate URL as explained below in the last step.

styles.css

.authorTable {   
   border-collapse:collapse;
   border-bottom:1px solid #000000;
}

.authorTableHeader {
   text-align:center;
   background:none repeat scroll 0 0 #B5B5B5;
   border-bottom:1px solid #000000;
   border-top:1px solid #000000;
   padding:2px;
}

.authorTableOddRow {
   text-align:center;
   background:none repeat scroll 0 0 #FFFFFFF;	
}

.authorTableEvenRow {
   text-align:center;
   background:none repeat scroll 0 0 #D3D3D3;
}

pom.xml

<project xmlns = "http://maven.apache.org/POM/4.0.0" 
   xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation = "http://maven.apache.org/POM/4.0.0
   http://maven.apache.org/maven-v4_0_0.xsd">
   
   <modelVersion>4.0.0</modelVersion>
   <groupId>com.tutorialspoint.test</groupId>
   <artifactId>helloworld</artifactId>
   <packaging>war</packaging>
   <version>1.0-SNAPSHOT</version>
   <name>helloworld Maven Webapp</name>
   <url>http://maven.apache.org</url >
   
   <dependencies>
      <dependency>
         <groupId>junit</groupId>
         <artifactId>junit</artifactId>
         <version>3.8.1</version>
         <scope>test</scope>
      </dependency>
      
      <dependency>
         <groupId>com.sun.faces</groupId>
         <artifactId>jsf-api</artifactId>
         <version>2.1.7</version>
      </dependency>
      
      <dependency>
         <groupId>com.sun.faces</groupId>
         <artifactId>jsf-impl</artifactId>
         <version>2.1.7</version>
      </dependency>
      
      <dependency>
         <groupId>javax.servlet</groupId>
         <artifactId>jstl</artifactId>
         <version>1.2</version>
      </dependency>
      
      <dependency>
        <groupId>postgresql</groupId>
        <artifactId>postgresql</artifactId>
        <version>9.1-901.jdbc4</version>
     </dependency>
   </dependencies>
   
   <build>
      <finalName>helloworld</finalName>
      <plugins>
         <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>2.3.1</version>
            <configuration>
               <source>1.6</source>
               <target>1.6</target>
            </configuration>
         </plugin>
         
         <plugin>
            <artifactId>maven-resources-plugin</artifactId>
            <version>2.6</version>
            <executions>
               <execution>
                  <id>copy-resources</id>
                  <phase>validate</phase>
                  <goals>
                     <goal>copy-resources</goal>
                  </goals>
                  
                  <configuration>
                     <outputDirectory>${basedir}/target/helloworld/resources
                        </outputDirectory>
                     <resources>          
                        <resource>
                           <directory>src/main/resources</directory>
                           <filtering>true</filtering>
                        </resource>
                     </resources>              
                  </configuration>            
               </execution>
            </executions>
         </plugin>
      
      </plugins>
   </build>
</project>

Author.java

package com.tutorialspoint.test;

public class Author {
   int id;
   String name;
   
   public String getName() {
      return name;
   }
   
   public void setName(String name) {
      this.name = name;
   }
   
   public int getId() {
      return id;
   }
   
   public void setId(int id) {
      this.id = id;
   }
}

UserData.java

package com.tutorialspoint.test;

import java.io.Serializable;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import java.util.ArrayList;
import java.util.List;

import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
import javax.faces.event.ComponentSystemEvent;

@ManagedBean(name = "userData", eager = true)
@SessionScoped
public class UserData implements Serializable {
   private static final long serialVersionUID = 1L;

   public List<Author> getAuthors() {
      ResultSet rs = null;
      PreparedStatement pst = null;
      Connection con = getConnection();
      String stm = "Select * from authors";
      List<Author> records = new ArrayList<Author>();
      
      try {   
         pst = con.prepareStatement(stm);
         pst.execute();
         rs = pst.getResultSet();

         while(rs.next()) {
            Author author = new Author();
            author.setId(rs.getInt(1));
            author.setName(rs.getString(2));
            records.add(author);				
         }
      } catch (SQLException e) {
         e.printStackTrace();
      }
      return records;
   }

   public Connection getConnection() {
      Connection con = null;
      String url = "jdbc:postgresql://localhost/testdb";
      String user = "user1";
      String password = "user1";
      
      try {
         con = DriverManager.getConnection(url, user, password);
         System.out.println("Connection completed.");
      } catch (SQLException ex) {
         System.out.println(ex.getMessage());
      }
      
      finally {
      }
      return con;
   }
}

home.xhtml

<?xml version = "1.0" encoding = "UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns = "http://www.w3.org/1999/xhtml"
   xmlns:f = "http://java.sun.com/jsf/core"    
   xmlns:h = "http://java.sun.com/jsf/html">
   
   <h:head>
      <title>JSF Tutorial!</title>
      <h:outputStylesheet library = "css" name = "styles.css"  /> 
   </h:head>
   
   <h:body>
      <h2>JDBC Integration Example</h2>
      
      <h:dataTable value = "#{userData.authors}" var = "c"
         styleClass = "authorTable"
         headerClass = "authorTableHeader"
         rowClasses = "authorTableOddRow,authorTableEvenRow">
         
         <h:column><f:facet name = "header">Author ID</f:facet>
            #{c.id}
         </h:column>
         
         <h:column><f:facet name = "header">Name</f:facet>
            #{c.name}
         </h:column>
      </h:dataTable>
   </h:body>
</html>

完成所有更改後，讓我們像在JSF-First應用程式一章中那樣編譯和運行應用程式。如果您的應用程式一切正常，這將產生以下結果。