B1. Tao Project
B2. Tao API
	CalculatorAPI => CalculatorWS
	CalculatorAPI -> cong, tru, nhan, chia
		-> Input: x, y => du lieu dau vao
		-> Output: ket qua
B3. Trien khai
	- Tao Web Service
	- Build
	- WSDL => Tuong ung vs 1 API

-----------------------------------------
Lam vi du: Tao API >> StudentWS
	- lay danh sach sinh vien
	- them/sua/xoa sinh vien
	
create table student (
	id int primary key auto_increment,
	name varchar(50),
	address varchar(200),
	email varchar(150),
	gender varchar(15)
)

#Student.java

/*
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 * and open the template in the editor.
 */
package entities;

import java.io.Serializable;
import javax.persistence.Basic;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.Table;
import javax.validation.constraints.Size;
import javax.xml.bind.annotation.XmlRootElement;

/**
 *
 * @author teacher
 */
@Entity
@Table(name = "student")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "Student.findAll", query = "SELECT s FROM Student s")
    , @NamedQuery(name = "Student.findById", query = "SELECT s FROM Student s WHERE s.id = :id")
    , @NamedQuery(name = "Student.findByName", query = "SELECT s FROM Student s WHERE s.name = :name")
    , @NamedQuery(name = "Student.findByAddress", query = "SELECT s FROM Student s WHERE s.address = :address")
    , @NamedQuery(name = "Student.findByEmail", query = "SELECT s FROM Student s WHERE s.email = :email")
    , @NamedQuery(name = "Student.findByGender", query = "SELECT s FROM Student s WHERE s.gender = :gender")})
public class Student implements Serializable {

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "id")
    private Integer id;
    @Size(max = 50)
    @Column(name = "name")
    private String name;
    @Size(max = 200)
    @Column(name = "address")
    private String address;
    // @Pattern(regexp="[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?", message="Invalid email")//if the field contains email address consider using this annotation to enforce field validation
    @Size(max = 150)
    @Column(name = "email")
    private String email;
    @Size(max = 15)
    @Column(name = "gender")
    private String gender;

    public Student() {
    }

    public Student(Integer id) {
        this.id = id;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (id != null ? id.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {
        // TODO: Warning - this method won't work in the case the id fields are not set
        if (!(object instanceof Student)) {
            return false;
        }
        Student other = (Student) object;
        if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "entities.Student[ id=" + id + " ]";
    }
    
}

#CalculatorWS.java

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

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

/**
 *
 * @author teacher
 */
@WebService(serviceName = "CalculatorWS")
public class CalculatorWS {

    /**
     * This is a sample web service operation
     */
    @WebMethod(operationName = "xinchao")
    public String hello(@WebParam(name = "name") String txt) {
        return "Hello " + txt + " !";
    }
    
    @WebMethod
    public float cong(float x, float y) {
        return x+y;
    }
    
    @WebMethod
    public float tru(float x, float y) {
        return x-y;
    }
    
    @WebMethod
    public float nhan(float x, float y) {
        return x*y;
    }
    
    @WebMethod
    public float chia(float x, float y) throws Exception {
        if(y == 0) {
            throw new Exception("Error >> chia cho 0");
        }
        return x/y;
    }
}

#StudentWS.java

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package ws;

import entities.Student;
import java.util.List;
import javax.jws.WebService;
import javax.jws.WebMethod;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;

/**
 *
 * @author teacher
 */
@WebService(serviceName = "StudentWS")
public class StudentWS {
    @WebMethod
    public List<Student> getStudentList() {
        EntityManagerFactory factory = Persistence.createEntityManagerFactory("ExampleWSPU");
        EntityManager em = factory.createEntityManager();
        
        Query q = em.createNamedQuery("Student.findAll", Student.class);
        return q.getResultList();
    }
    
    @WebMethod
    public String addStudent(String name, String address, String email, String gender) {
        EntityManagerFactory factory = Persistence.createEntityManagerFactory("ExampleWSPU");
        EntityManager em = factory.createEntityManager();
        
        Student std = new Student();
        std.setName(name);
        std.setAddress(address);
        std.setEmail(email);
        std.setGender(gender);
        
        em.getTransaction().begin();
        em.persist(std);
        em.getTransaction().commit();
        
        return "success";
    }
    
    @WebMethod
    public String removeStudent(int id) {
        EntityManagerFactory factory = Persistence.createEntityManagerFactory("ExampleWSPU");
        EntityManager em = factory.createEntityManager();
        
        Student std = em.find(Student.class, id);
        
        em.getTransaction().begin();
        em.remove(std);
        em.getTransaction().commit();
        
        return "success";
    }
}

#persistence.xml

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
  <persistence-unit name="ExampleWSPU" transaction-type="RESOURCE_LOCAL">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <class>entities.Student</class>
    <properties>
      <property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/student_manager?serverTimezone=UTC"/>
      <property name="javax.persistence.jdbc.user" value="root"/>
      <property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
      <property name="javax.persistence.jdbc.password" value=""/>
    </properties>
  </persistence-unit>
</persistence>