1. Web Service

#CalculatorWS.java

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package aptech.ws;

import javax.jws.WebService;
import javax.jws.WebMethod;
import javax.jws.WebParam;

/**
 * CalculatorWS -> WSDL (SOAP API) -> Gom cac API chuc nang.
 * @author DiepTV
 */
@WebService(serviceName = "CalculatorWS")
public class CalculatorWS {

    /**
     * This is a sample web service operation
     * hello method -> tuong la 1 API de su dung sau nay.
     */
    @WebMethod(operationName = "hello")
    public String hello(@WebParam(name = "name") String txt) {
        return "Hello " + txt + " !";
    }
    
    @WebMethod
    public float cong(@WebParam(name = "x") float x, @WebParam(name = "y") float y) {
        return x + y;
    }
    
    @WebMethod(operationName = "api_calculator_tru")
    public float tru(@WebParam(name = "param1") float x, @WebParam(name = "param2") float y) {
        return x - y;
    }
    
    @WebMethod
    public float nhan(@WebParam(name = "x") float x, @WebParam(name = "y") float y) {
        return x * y;
    }
    
    @WebMethod
    public float chia(@WebParam(name = "x") float x, @WebParam(name = "y") float y) throws Exception {
        if(y == 0) {
            throw new Exception("Yeu cau y khac 0");
        }
        return x/y;
    }
}

#TestWebService.java

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 * and open the template in the editor.
 */
package aptech.ws;

import javax.jws.WebService;
import javax.jws.WebMethod;
import javax.jws.WebParam;

/**
 *
 * @author DiepTV
 */
@WebService(serviceName = "TestWebService")
public class TestWebService {

    /**
     * This is a sample web service operation
     */
    @WebMethod(operationName = "hello")
    public String hello(@WebParam(name = "name") String txt) {
        return "Hello " + txt + " !";
    }
}

#CalculatorAPI.java

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package aptech;

/**
 *
 * @author DiepTV
 */
public class CalculatorAPI {

    public static float cong(float x, float y) {
        aptech.CalculatorWS_Service service = new aptech.CalculatorWS_Service();
        aptech.CalculatorWS port = service.getCalculatorWSPort();
        return port.cong(x, y);
    }

    public static float tru(float x, float y) {
        aptech.CalculatorWS_Service service = new aptech.CalculatorWS_Service();
        aptech.CalculatorWS port = service.getCalculatorWSPort();
        return port.apiCalculatorTru(x, y);
    }

    public static float nhan(float x, float y) {
        aptech.CalculatorWS_Service service = new aptech.CalculatorWS_Service();
        aptech.CalculatorWS port = service.getCalculatorWSPort();
        return port.nhan(x, y);
    }

    public static float chia(float x, float y) throws Exception_Exception {
        aptech.CalculatorWS_Service service = new aptech.CalculatorWS_Service();
        aptech.CalculatorWS port = service.getCalculatorWSPort();
        return port.chia(x, y);
    }
    
}

#Main.java

/*
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 */
package aptech;

import java.util.Scanner;

/**
 *
 * @author DiepTV
 */
public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        
        System.out.println("Nhap x: ");
        float x = scan.nextFloat();
        
        System.out.println("Nhap y: ");
        float y = scan.nextFloat();
        
        float result = CalculatorAPI.cong(x, y);
        System.out.println("Result: " + result);
    }
}