【Axis2】Java Web Services 資料庫範例

這邊來介紹 Java Web Services 存取資料庫的範例

以下 demo 的資料庫是用 SQL Server  所以要先去下載適當的 JDBC Driver

下載下來後將JAR檔放到 Tomcat 5.5 安裝目錄下的 common\lib 裡面

接著要設定資料庫連線的參數

一樣開啟 Tomcat 5.5 安裝目錄下的 webapps\axis2\WEB-INF\conf\axis2.xml 檔案

並將以下相關參數寫入

<parameter name="DB_driverClassName">com.microsoft.sqlserver.jdbc.SQLServerDriver</parameter>

<parameter name="DB_url">jdbc:sqlserver://xxx.xxx.xx.xxx:1400;DatabaseName=test</parameter>

<parameter name="DB_username">XXXX</parameter>

<parameter name="DB_password">123456</parameter>

完成之後建立一個 Server 端的程式  開啟 Eclipse

左上角的 File →New→ Java Project ，在Project name 輸入 WS2MSSQL，並按下 next

完成後第一步要先將 Axis2 的 library 匯入

接著要建立資料庫的連線  首先建立一個新的 Java class  

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import org.apache.axis2.context.ConfigurationContext;
import org.apache.axis2.description.AxisService;
import org.apache.axis2.engine.ServiceLifeCycle;

public class DBtestServiceLifeCycle implements ServiceLifeCycle {
        public static final String DB_CONNECTION = "connKey";

        public void shutDown(ConfigurationContext configctx, AxisService service) {
                // TODO Auto-generated method stub
               Connection conn = (Connection) configctx.getProperty(DB_CONNECTION);
               if (conn != null) {
                       try {
                               // 關閉資料庫連線
                               conn.close();
                        } catch (SQLException e) {
                                System.out.println("Error while closing the DB connection");
                        }
               }

        }

        public void startUp(ConfigurationContext configctx, AxisService service) {
                // TODO Auto-generated method stub
                // 從axis2.xml讀取四個連線參數
  String DB_driverClassName = 
    (String) service.getAxisConfiguration().getParameterValue("DB_driverClassName");
                String DB_url = 
    (String) service.getAxisConfiguration().getParameterValue("DB_url");
                String DB_username = 
    (String) service.getAxisConfiguration().getParameterValue("DB_username");
                String DB_password = 
    (String) service.getAxisConfiguration().getParameterValue("DB_password");

                try {
                        Class.forName(DB_driverClassName);
                        Connection conn = DriverManager.getConnection(DB_url, DB_username,DB_password);
                        configctx.setProperty(DB_CONNECTION, conn);
                } catch (Exception e) {
                        System.out.println(e.getMessage());
                        e.printStackTrace();
                }
        }

}

資料連接部分完成後 這個 Demo 理的資料庫有一個 Table：t_dept


所以接下來先建立一個 Java bean 

import java.util.Date;
public class Dept 
{
        private String deptid; 
        private String dept_cname; 
        private String dept_fullname;
        private String dept_no;
        
        //省略 getter/setter
}

接著建立存取資料庫的 DAO  首先先建立 DAOBase 這個抽象類別

import java.sql.Connection;
import org.apache.axis2.context.MessageContext;
public abstract class DAOBase 
{
        protected Connection getConnByAxis2RuntimeConfig(){
                return (Connection) MessageContext.getCurrentMessageContext().getProperty(
                        DBtestServiceLifeCycle.DB_CONNECTION);
        }
}

接著是 DeptDAO

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;

public class DeptDAO extends DAOBase
{
 public String QueryById(String deptId)
 {
  String deptName = null;
  Connection connection = getConnByAxis2RuntimeConfig();
  if(connection !=null) {
            String SQL = "SELECT dept_cname FROM t_dept WHERE deptid = '" + deptId + "'";
            try {
                PreparedStatement statement = connection.prepareStatement(SQL);
                ResultSet rs = statement.executeQuery();
                if(rs.next()) {
                 deptName = rs.getString("dept_cname");
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }
     }
  return deptName;
 }
 
 public Dept[] listAllDept()
 {
  ArrayList list = new ArrayList();
  Dept dept =  null;
  Connection connection = getConnByAxis2RuntimeConfig();
  if(connection !=null) {
   String SQL = "SELECT * FROM t_dept";
   try{
    PreparedStatement statement = connection.prepareStatement(SQL);
    ResultSet rs = statement.executeQuery();
    while(rs.next()){
     dept = new Dept();
     dept.setDeptid(rs.getString("deptid"));
              dept.setDept_cname(rs.getString("dept_cname"));
              dept.setDept_fullname(rs.getString("dept_fullname"));
              dept.setDept_no(rs.getString("dept_no"));
              list.add(dept);
    }
   }catch(SQLException e){
    e.printStackTrace();
   }
  
  }
  return (Dept[])list.toArray(new Dept[list.size()]);
 }
}

接下來建立一個 Service 

public class DeptWSevices 
{
 private DeptDAO deptDao;
 
 public DeptWSevices(){
  deptDao = new DeptDAO();
 }
 
 public String getDeptById(String deptId){
  return this.deptDao.QueryById(deptId);
 }
 
 public Dept[] listAllDept(){
  return this.deptDao.listAllDept();
 }
}

最後在撰寫以下 services.xml


在 project 目錄下建立一個 META-INF 的資料夾

<service name="DBSampleService" class="DBtestServiceLifeCycle">

     <description>

         DB sample for Web Service

     </description>

     <messageReceivers>

         <messageReceiver mep="http://www.w3.org/2004/08/wsdl/in-only"

              class="org.apache.axis2.rpc.receivers.RPCInOnlyMessageReceiver" />

         <messageReceiver mep="http://www.w3.org/2004/08/wsdl/in-out"

              class="org.apache.axis2.rpc.receivers.RPCMessageReceiver" />

     </messageReceivers>

     <parameter name="ServiceClass">

         DeptWSevices

     </parameter>

</service>

完成後同樣打包成 war 或 aar 檔 並儲存


接著開啟 Tomcat 5.5  將剛剛這包 war 或 aar 檔上傳  


過程不會的話可以看這篇 【Axis2】Java Web Services 範例

上傳完成並無錯誤後就可以撰寫一個簡單的 Client 進行測試


同樣的 Client  端的細節可以看上一篇

public static void main(String[] args) throws RemoteException {
 // TODO Auto-generated method stub
 DBSampleServiceStub stub = new DBSampleServiceStub();
 ListAllDeptResponse response = stub.listAllDept();  //這裡呼叫了 listAllDept method
 Dept[] depts = response.get_return();
 for(Dept d : depts){
  System.out.println("dept : " + d.getDept_cname());
 }
}