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Java RPC style Webservice with JAX-WS

We have to create two projects one is WebService server project and WebService client project, here client will call the methods of Server.

1. Creating Server project:

Create an interface with @WebService annotation, and annotate the method with @WebMethod whitch you wanted to expose as web service.

package com.java2practice.ws;
import javax.jws.WebMethod;
import javax.jws.WebService;
import javax.jws.soap.SOAPBinding;
import javax.jws.soap.SOAPBinding.Style;

@WebService
@SOAPBinding(style = Style.RPC)
public interface WebServiceInterface{
@WebMethod
int sum(int firstNumber, int secondNumber);
}

2. Create an implementation to the above interface  like below

package com.java2practice.ws;
import javax.jws.WebService;
@WebService(endpointInterface = "com.java2practice.ws.WebServiceInterface")
public class WebServiceImpl implements WebServiceInterface{
@Override
public int sum(int firstNumber, int secondNumber) {
return firstNumber + secondNumber;
}
}

3. Now we have to publish this webservice by using EndPoint.

package com.java2practice.ws;
import javax.xml.ws.Endpoint;
import com.java2practice.ws.WebServiceImpl;

public class WebServicePublisher{

public static void main(String[] args) {

Endpoint.publish("http://localhost:7777/webservice/testws", new WebServiceImpl());
}
}

 

  1. When we run the above code, webservice will be published and can be accessed by using http://localhost:7777/webservice/testws URL.
  2. To see the generated WSDL file click http://localhost:7777/webservice/testws?wsdl. And the generated WSDL look like
<pre>-<!-- Published by JAX-WS RI at http://jax-ws.dev.java.net. RI's version is JAX-WS RI 2.2.4-b01. -->
<!-- Generated by JAX-WS RI at http://jax-ws.dev.java.net. RI's version is JAX-WS RI 2.2.4-b01. -->
<definitions targetNamespace="http://ws.java2practice.com/" name="WebServiceImplService"><types/>
<message name="sum"><part name="arg0" type="xsd:int"/><part name="arg1" type="xsd:int"/></message>
<message name="sumResponse"><part name="return" type="xsd:int"/></message>
<portType name="WebServiceInterface"><operation name="sum" parameterOrder="arg0 arg1">
<input wsam:Action="http://ws.java2practice.com/WebServiceInterface/sumRequest" message="tns:sum"/>
<output wsam:Action="http://ws.java2practice.com/WebServiceInterface/sumResponse" message="tns:sumResponse"/>
</operation></portType><binding name="WebServiceImplPortBinding" type="tns:WebServiceInterface">
<soap:binding transport="http://schemas.xmlsoap.org/soap/http" style="rpc"/>
<operation name="sum"><soap:operation soapAction=""/>
<input>
<soap:body use="literal" namespace="http://ws.java2practice.com/"/>
</input>
<output>
<soap:body use="literal" namespace="http://ws.java2practice.com/"/>
</output>
</operation>
</binding>
<service name="WebServiceImplService">
<port name="WebServiceImplPort" binding="tns:WebServiceImplPortBinding">
<soap:address location="http://localhost:7777/webservice/testws"/>
</port>
</service>
</definitions>

 

Our webservice server project is fine, now we have to create client program, for this we have to use wsimport command, this will be available in java.

  1. Go to command prompt and give wsimport it will show all the options which are there in wsimport, if it doesn’t show any thing set the path variable to jdk/bin.
  2. wsimport -keep http://localhost:7777/webservice/testws?wsdl -d D:\java2practice\Desktop\client
  3. It will generate the files, and copy those files to your IDE and create a client program like below.

package com.java2practice.ws;

public class WebServiceClient {

public static void main(String[] args) {

WebServiceImplService service = new WebServiceImplService();

WebServiceInterface serviceInterface = service.getWebServiceImplPort();

int sum = serviceInterface.sum(10, 20);

System.out.println("answer : "+sum);//outputs answer as 30

}

}

Thanks for reading.

 

Categories: Java, WebService

How to send multiple rows of data to Spring Controller

March 1, 2014 1 comment

Common requirement would be sending multiple rows of data to Spring Controller.

We use @RequestParam String value to hold the single form field. But when we dealing with multiple rows @RequestParam String value won’t work.

If It is single row like below like below

S.NO First Name Last Name Age
1 AAA BBB 23

We can use @RequestParam annotation to capture the form data:

public String saveEmployee(@RequestParam Integer sNo, @RequestParam String firstName, @RequestParam String firstName, @RequestParam Integer age){
//here we can access the form data.
}

Suppose we have a form with multiple rows. Then We have to use @RequestParam String[] values,

Let’s see the example below:

S.NO First Name Last Name Age
1 AAA BBB 23
2 CCC DDD 24
3 EEE FFF 28

And here is the Controller Code:


public String saveEmployees(@RequestParam Integer[] sNo, @RequestParam[] String firstName, @RequestParam[] String lastName, @RequestParam[] Integer age){

 //first row data
 Integer sNo_0 = sNo[0];
 String firstName_0 = firstName[0];
 String lastName_0 = lastName[0];
 Integer age_0 = age[0];

//second row data

 Integer sNo_1 = sNo[1];
 String firstName_1 = firstName[1];
 String lastName_1 = lastName[1];
 Integer age_1 = age[1];

//third row data

 Integer sNo_2 = sNo[2];
 String firstName_2 = firstName[2];
 String lastName_2 = lastName[2];
 Integer age_2 = age[2];
 }

Thanks for reading.

Categories: SQL

How to start Weblogic Server when any one of the Data Source is down

February 25, 2014 Leave a comment

Recently we came across an issue with Weblogic start up, we configured Weblogic server with multiple DataSources and one of our Database is down due to some network issue. Weblogic server is unable to start as one of the DataSource is down, but to delete the DataSource (not working one) we need to have Weblogic server started, To start the server every DataSource should work fine. It’s  a deadlock.

Solution : All the DataSources related configuration files located in (beahome)\user_projects\domains\Your_Domain\config\jdbc, Copy the working DataSource details jdbc_url,username,pwd(it will be in encrypted format) and paste it in another DataSource configuration xml file which database is down.

Suppose we have two DataSources

  1. DATASOURCE_1
  2. DATASOURCE_2

If DATASOURCE_1 is not working, we can copy the jdbc-url, username,pwd from DATASOURCE_2 and paste it in DATSOURCE_1 configuration file.

And start weblogic server now, it will start normally.

What we did here is just manipulated weblogic with the same jdbc details with multiple DataSources, internally it will treat as multiple DataSources, but it will connect to only working database as we gave the jdbc details of this working database.

Though we have two DataSources named with DATSOURCE_1 and DATASOURCE_2, both are pointing to same database DATSOURCE_2.

Thanks for reading, hope it helps.

Categories: Java, Weblogic

How to execute method with JSP EL tag?

February 20, 2014 Leave a comment

Till JSP 2.1 by using property name on bean <c:out value=”${beanName.property}”/> we used to display the values, internally it will call getter method of that property and value will be printed to browser. But to execute a normal method which doesn’t have getter method or setter method is not possible till JSP 2.1.

if we write <c:out value=”${beanName.methodName}”/> it will throw an error saying : getMethodName is not existing in type beanName.

But from JSP 2.2 on wards we can write <c:out value=”${beanName.methodName}”/> and it will execute the method internally and outputs the results to browser.

This feature is available in Servlet 3.0 environment, Tomcat 7 implementing Servlet 3.0 so we can run this code in Tomcat 7.

Thanks for reading

Categories: Java Tags:

Javascript : modular pattern

February 16, 2014 Leave a comment

While writing javascript code as a beginner we just write

function hello(){
alert('hello world');
}

but some problems occur with this approach, when we include multiple js files. All the variables which are declared outside any function will be treated as global and can be accessed from any function. And all the functions in all the js files are local to each other that means we can call any function from any js file, there is no concept of private function or we can not hide any function from being called.

With Javascript modular pattern we can avoid all these.

In this pattern we assign an anonymous function to global variable and all the functions declared inside can be called by using the variable name and the function name.

var app = (function (){

})();

Here app is the global variable and an anonymous function is assigned to it.

var app = (function (){
    return {
       publicFun : function(){
              alert('public function');
             }
    };
})();

Declared a function with name publicFun, to access this function we have to call with global variable name app.publicFun(); and it will alert with “public function”.

Private functions: Whatever the functions we returned from the anonymous function can be accessed by using app global variable.

If we declare any function before return function, that will be called as local function and can not accessed with app variable.

var app = (function (){
    function privateFun(){
             alert('private function');
    }
    return {
       publicFun : function(){
              alert('public function');
             }
    };
})();

If we call app.privateFun(); will give an error : TypeError: app.privateFun is not a function

So these private functions can not be accessed out side of the anonymous block. But we can call these in side any other public  function.

var app = (function (){
    function privateFun(){
             alert('private function');
    }
    return {
       publicFun : function(){
              privateFun();
              alert('public function');
             }
    };
})();

Now app.publicFun() will internally call private function and will get private function alert followed by public function. Thanks for reading, hope you enjoyed it.

Categories: javascript

Spring Securty 3.2 with Custom Service

user table


CREATE TABLE 'user' (
'user_id' int(11) NOT NULL AUTO_INCREMENT,
'user_name' varchar(250) NOT NULL,
'password' varchar(250) DEFAULT NULL,
PRIMARY KEY ('user_id','user_name')
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=latin1

 

role table


CREATE TABLE 'role' (
'role_id' int(11) NOT NULL AUTO_INCREMENT,
'role_name' varchar(250) NOT NULL,
PRIMARY KEY ('role_id','role_name')
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=latin1

user_role join table

CREATE TABLE 'user_role' (
'user_id' int(11) NOT NULL,
'role_id' int(11) NOT NULL,
PRIMARY KEY ('user_id','role_id')
) ENGINE=InnoDB DEFAULT CHARSET=latin1

user and role has many to many relationship, and joining table is user_role

User.java

package com.java2practice.springsecurity.model;
import java.util.HashSet;
import java.util.Set;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;
import javax.persistence.Table;

@Entity
@Table(name="user")
public class User {
@Id
@GeneratedValue
@Column(name="user_id")
private Integer userId;

@Column(name="user_name")
private String userName;

@Column(name="password")
private String password;

@ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
@JoinTable(name = "user_role", joinColumns = {
@JoinColumn(name = "USER_ID", nullable = false, updatable = false) },
inverseJoinColumns = { @JoinColumn(name = "ROLE_ID",
nullable = false, updatable = false) })

private Set<Role> userRoles = new HashSet<Role>(0);

public Integer getUserId() {
return userId;
}
public void setUserId(Integer userId) {
this.userId = userId;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Set<Role> getUserRoles() {
return userRoles;
}
public void setUserRoles(Set<Role> userRoles) {
this.userRoles = userRoles;
}
}

Role.java

package com.java2practice.springsecurity.model;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name="role")
public class Role {
@Id
@GeneratedValue
@Column(name="role_id")
private Integer roleId;

@Column(name="role_name")
private String roleName;

public Integer getRoleId() {
return roleId;
}
public void setRoleId(Integer roleId) {
this.roleId = roleId;
}
public String getRoleName() {
return roleName;
}
public void setRoleName(String roleName) {
this.roleName = roleName;
}
}

UserDao.java

package com.java2practice.springsecurity.dao;
import javax.annotation.Resource;
import org.apache.log4j.Logger;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.criterion.Restrictions;

import com.java2practice.springsecurity.model.User;

public class UserDao {
Logger logger = Logger.getLogger(this.getClass());

@Resource
SessionFactory sessionFactory;

public User getUser(String userName){
logger.info("getUser called");
Session session = null;
try{
session = sessionFactory.openSession();
User user = (User) session.createCriteria(User.class).
add(Restrictions.eq("userName", userName)).uniqueResult();
return user;
}catch (Exception e) {
e.printStackTrace();
return null;
}
}
}

Our service has to implement org.springframework.security.core.userdetails.UserDetailsService
it has one method
public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException
this method returns org.springframework.security.core.userdetails.UserDetails
UserDetails user = new User(“username”, “password”,true, true, true, true, authorities);
like this we can convert our User to Spring UserDetails.

UserDetailsServiceImpl.java


package com.java2practice.springsecurity.service;
import java.util.ArrayList;
import java.util.List;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.core.authority.GrantedAuthorityImpl;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.core.userdetails.UsernameNotFoundException;

import com.java2practice.springsecurity.dao.UserDao;
import com.java2practice.springsecurity.model.Role;

@SuppressWarnings("deprecation")
public class UserDetailServiceImpl implements UserDetailsService{

Logger logger = Logger.getLogger(getClass());

@Autowired
UserDao userDao;

@Override
public UserDetails loadUserByUsername(String username)
throws UsernameNotFoundException {
try{
logger.info("loadUserByUsername ");

com.java2practice.springsecurity.model.User userFromDB =  userDao.getUser(username);
logger.info("got user from database "+userFromDB);
List<GrantedAuthorityImpl> authorities = new ArrayList<GrantedAuthorityImpl>();

for(Role role : userFromDB.getUserRoles()){
authorities.add(new GrantedAuthorityImpl(role.getRoleName()));
}

UserDetails user = new User(userFromDB.getUserName(), userFromDB.getPassword(),
true, true, true, true, authorities);

return user;
}catch(Exception e){
logger.error("error "+e);
return null;
}
}
}

WebController.java

package com.java2practice.springsecurity.controller;
import org.apache.log4j.Logger;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class WebController {
Logger logger = Logger.getLogger(this.getClass());

@RequestMapping("/home")
public String home(){
logger.info("webcontroller");
return "home";
}
}

applicationContext.xml

<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:security="http://www.springframework.org/schema/security"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.2.xsd
http://www.springframework.org/schema/security
http://www.springframework.org/schema/security/spring-security.xsd">

<context:annotation-config />

<context:property-placeholder location="classpath:db.properties" />

<bean id="dataSource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${jdbc.driverClassName}" />
<property name="url" value="${jdbc.url}" />
<property name="username" value="${jdbc.user}" />
<property name="password" value="${jdbc.password}" />
</bean>

<bean id="sessionFactory"
class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="packagesToScan" value="com.java2practice.springsecurity.model" />
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.format_sql">true</prop>
</props>

</property>
</bean>

<!-- A custom service where Spring will retrieve users and their corresponding    access levels -->
<bean id="userDetailServiceImpl"   class="com.java2practice.springsecurity.service.UserDetailServiceImpl"     autowire="byName" />

<bean id="userDao" class="com.java2practice.springsecurity.dao.UserDao" autowire="byName" />

<!-- This is where we configure Spring-Security -->
<security:http auto-config="true" use-expressions="true">

<security:form-login login-page="/login.jsp"
authentication-failure-url="/login.jsp?error=true"
default-target-url="/home.html" />

</security:http>

<!-- Declare an authentication-manager to use a custom userDetailsService -->
<security:authentication-manager>
<security:authentication-provider
user-service-ref="userDetailServiceImpl">
</security:authentication-provider>
</security:authentication-manager>

</beans>

dispatcher-servlet.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">

<context:component-scan base-package="com.java2practice.springsecurity.controller" />
<context:annotation-config />

<bean id="viewResolver"
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix">
<value>/WEB-INF/jsp/</value>
</property>
<property name="suffix">
<value>.jsp</value>
</property>
</bean>
</beans>

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
id="WebApp_ID" version="2.5">
<display-name>Spring4MVC</display-name>
<welcome-file-list>
<welcome-file>login.jsp</welcome-file>
</welcome-file-list>

<servlet>
<servlet-name>dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>dispatcher</servlet-name>
<url-pattern>*.html</url-pattern>
</servlet-mapping>

<filter>
<filter-name>springSecurityFilterChain</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>

<filter-mapping>
<filter-name>springSecurityFilterChain</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>

<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:applicationContext.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<listener>
<listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
</listener>

</web-app>

login.jsp

<%@ taglib uri="http://www.springframework.org/tags/form" prefix="form"%>
<%@ taglib uri="http://www.springframework.org/tags" prefix="spring"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<h1>

<c:if test="${param.error}">
Error occurred ${param.error }
</c:if>

</h1>
Login
<form action="j_spring_security_check" method="post">

<p>

<label for="j_username">Username</label> <input id="j_username"
name="j_username" type="text" />
</p>
<p>

<label for="j_password">Password</label> <input id="j_password"
name="j_password" type="password" />
</p>
<input type="submit" value="Login" />

</form>
</body>
</html>

home.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Home</title>
</head>
<body>

<h1>Welcome to Spring Security</h1>
</body>
</html>

Project Structure

spring_security_project_structure

Categories: Spring

SQL Joins explained in simple terms

Joins are used to join two or more tables in SQL based on the common data.
In this post I have explained below joins

1. Inner Join
2. Left outer join
3. Right outer join

Example:  Let’s say we have an Employee table and Department table. Where every employee is associated with Department, new employees many not have Department.
And Every Department will have employees, for new Department, employees may not be there.

Department Table with data:
department_tableEmployee table with data:
employee_data

Here department_id is the foreign key to Department table, Department 3 doesn’t have any employees associated with it.  And Employees 4,5 are not associated with any Department.

Now will perform different type of joins and examine the results:

1. Inner Join: Intersection of two tables is called inner join, Only the matched data will be returned from the two tables

Query: select e.*, d.* from employee e inner join department d on e.department_id = d.id
Resulted data :
inner_join

The employees who doesn’t have any department and Department which doesn’t have employees won’t be returned.
In Venn diagram it looks like this:

inner_join_first
2. Left outer join: returns all the data from the left table and only matched data from the right table.

Query: select e.*, d.* from employee e left outer join department d on e.department_id = d.id
Resulted data :
left_outer_join

Returns all the 5 records from the Employee table and only 3 records from the Department table.
In the place of Department details for the employees 4,5( who doesn’t have department associated ) gives NULL values:
Venn diagram looks like this:
left_outer_join_venn

If we do left outer join from Department to Employee the result would be:
Query:  select  d.*, e.* from  department d left outer join employee e on  d.id = e.department_id

Resulted Data:

left_outer_join_reverse
Returns all the data from Department table and in the place of employee details for Department 3 gives NULL values:

3. Right Outer Join:

Returns all the data from right side table and only matched data from the left side table.
Query: select e.*, d.* from employee e right outer join department d on e.department_id = d.id

Resulted data:

right_outer_join

Returned all records from Department table and NULL values in the place Department 3 as no employees associated with it.
Venn diagram looks like this:
right_outer_join_venn

Thanks for reading.

Categories: SQL