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Project Initialization

This chapter will use NetBeans as the IDE. Before we started,please make sure you have downloaded and installed NetBeans. Create a Java Class Library project with nepenthes-demo-3.0 name. nepenthes-demo-3.0.zip

Add the following libs to the project Libraries.

• nepenthes-3.0.jar
• servlet-api.jar (Located at /usr/local/apache-tomcat-7.0.55/lib)

Create the following packages in the project.

• com.yourcompany.bl
• com.yourcompany.schema
• com.yourcompany.service

Schema Object

According to Nepenthes protocol,database mapping object is table name with Schema suffix. Here we will create a class UserSchema.java to show you all kinds of field types that supported by Nepenthes.

package com.yourcompany.schema;

public class UserSchema 
{
    public int ID=0;
    public String Name="";
    public String Gender="";
    public int Age=0;
    public double Height=0.00;
    public String Birthdate="";
    public String Demo="";
    public String RegisterTime="";
}

BL Object

Business Logic Objec to manipulate database via Schema Object,the parent class BLGeneral provides all the operations including create the table if not exists.

package com.yourcompany.bl;

import java.sql.Connection;
import org.everdow.nepenthes.bl.BLGeneral;

public class BLUser extends BLGeneral
{
    private final String createSQL="Name VARCHAR(30),"+
                                   "Gender CHAR(1),"+
                                   "Age INT,"+
                                   "Height DECIMAL(4,2),"+
                                   "Birthdate DATE,"+
                                   "Memo TEXT,"+
                                   "RegisterTime DATETIME";
    
    private final String indexSQL="Name,Gender";
    
    public BLUser(Connection con) 
    {
        super(con);
        super.init(createSQL, indexSQL);
    }
}

Service Object

Provides service with JSON for iOS/Mac remote invoke. Service Object is wrapped as Servlet.

package com.yourcompany.service;

import com.yourcompany.bl.BLUser;
import com.yourcompany.schema.UserSchema;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.naming.NamingException;
import org.everdow.nepenthes.service.ServiceServlet;

public class UserService extends ServiceServlet
{
    @Override
    public void init()
    {
        try 
        {
            this.schema=new UserSchema();
            this.blGeneral=new BLUser(this.getConnection());
        } 
        catch (NamingException | SQLException ex) 
        {
            Logger.getLogger(UserService.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

Service Finalization

You need to complete the following steps to enable the service functional.

• Build the project
• Swith Projects panel to Files
  
• Right click to show Context Menu:Tool->Show In Finder
  
• Copy nepenthes-demo-3.0.jar to /usr/local/apache-tomcat-7.0.55/webapps/NepenthesDemo/WEB-INF/lib
• open /usr/local/apache-tomcat-7.0.55/webapps/NepenthesDemo/WEB-INF/web.xml,add the following contents. <!--UserService--> <servlet> <servlet-name>UserService</servlet-name> <servlet-class>com.yourcompany.service.UserService</servlet-class> </servlet> <servlet-mapping> <servlet-name>UserService</servlet-name> <url-pattern>/UserService</url-pattern> </servlet-mapping>
• Now web.xml has the following contents,please verify with yours. <?xml version="1.0" encoding="ISO-8859-1"?> <web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" version="2.4"> <display-name>NepenthesDemo</display-name> <description>Welcome to NepenthesDemo</description> <context-param> <param-name>DBCP</param-name> <param-value>jdbc/NepenthesDemo</param-value> </context-param> <resource-ref> <description>DB Connection</description> <res-ref-name>jdbc/NepenthesDemo</res-ref-name> <res-type>javax.sql.DataSource</res-type> <res-auth>Container</res-auth> </resource-ref> <!--ServicePassword--> <context-param> <param-name>ServicePassword</param-name> <param-value>12345678</param-value> </context-param> <!--UserService--> <servlet> <servlet-name>UserService</servlet-name> <servlet-class>com.yourcompany.service.UserService</servlet-class> </servlet> <servlet-mapping> <servlet-name>UserService</servlet-name> <url-pattern>/UserService</url-pattern> </servlet-mapping> </web-app>
• To make sure UserService enabled properly,please restart Tomcat. Open Terminal,execute the following commands.

  /usr/local/apache-tomcat-7.0.55/bin
  sudo ./shutdown.sh
  sudo ./startup.sh

• Here you have alread developed backend service for table User.