Java

Different ways to define a JavaScript class

Everything" in JavaScript is an Object: a String, a Number, an Array, a Function....
In addition, JavaScript allows you to define your own objects.
JavaScript is a very flexible object-oriented language when it comes to syntax
It's important to note that there are no classes in JavaScript.
Functions can be used to somewhat simulate classes, but in general JavaScript is a class-less language. Everything is an object.
And when it comes to inheritance, objects inherit from objects, not classes from classes

JavaScript is an object oriented language, but JavaScript does not use classes.
In JavaScript you don't define classes and create objects from these classes (as in most other object oriented languages).
JavaScript is prototype based, not class based.

Creating JavaScript Objects
There are 2 different ways to create a new object:

1. Use a function to define an object, then create new object instances.
2. Define and create a direct instance of an object.

1. Using a function
This is probably one of the most common ways. You define a normal JavaScript function and then create an object by using the new keyword. To define properties and methods for an object created using function(), you use the this keyword, as seen in the following example.

function Employee (empId,age,salary) {
this.empId = empId,
this.age = age,
this.salary = salary,
this.getInfo = getImpInfo;
}

function getImpInfo() {
return this.empId + ' ' + this.age + ' '+ this.salary;
}
Call this via
var emp = new Employee('EMP123','32','10000');
alert(emp.getInfo());

You can still call like this as well Employee('EMP123','32','10000');

1.1. Methods defined internally
In the example above you see that the method getInfo() of the Employee "class" was defined in a separate function getImpInfo(). While this works fine, it has one drawback – you may end up defining a lot of these functions and they are all in the "global namespece". This means you may have naming conflicts if you (or another library you are using) decide to create another function with the same name. The way to prevent pollution of the global namespace, you can define your methods within the constructor function, like this:

function Employee (empId,age,salary) {
this.empId = empId,
this.age = age,
this.salary = salary,
this.getInfo = function(){ return this.empId + ' ' + this.age + ' '+ this.salary;
};
}
Call this via
var emp = new Employee('EMP123','32','10000');
alert(emp.getInfo());
or call directly like
alert(new Employee('EMP123','32','10000').getImpInfo());

1.2. Methods added to the prototype
A drawback of 1.1. is that the method getInfo() is recreated every time you create a new object. Sometimes that may be what you want, but it's rare. A more inexpensive way is to add getInfo() to the prototype of the constructor function.

function Employee (empId,age,salary) {
this.empId = empId,
this.age = age,
this.salary = salary

}

Employee.prototype.getImpInfo = function() {
return this.empId + ' ' + this.age + ' '+ this.salary;
};
Call this using
var emp = new Employee('EMP123','32','10000');
alert(emp.getImpInfo());
or call directly like
alert(new Employee('EMP123','32','10000').getImpInfo());

2. Using object literals
Literals are shorter way to define objects and arrays in JavaScript. To create an empty object use the below:
var obj = {};
instead of the "normal" way:
var obj = new Object();
For arrays you can do:
var a = [];
instead of:
var a = new Array();
So you can skip the class-like stuff and create an instance (object) immediately. Here's the same functionality as described in the previous examples, but using object literal syntax this time:

var Employee = {
empId : "Emp123",
age : 32,
salary : 1000,
getInfo : function() {
return this.empId + ' ' + this.age + ' '+ this.salary;
}
}

OR Create an empty object and then add the properties
var Employee = new Object();
Employee.empId='Emp123';
etc...

Call this like
alert(Employee.getInfo() );

3. Singleton using a function
The third way presented in this article is a combination of the other two you already saw. You can use a function to define a singleton object. Here's the syntax:

The third way presented in this article is a combination of the other two you already saw. You can use a function to define a singleton object. Here's the syntax:

var Employee = new function (){
this.empId = "Emp123",
this.age = 32,
this.salary = 1000,
this.getInfo = function() {
return this.empId + ' ' + this.age + ' '+ this.salary;
};
}
call me like
alert(Employee.getInfo() );

new function(){...} does two things at the same time: define a function (an anonymous constructor function) and invoke it with new.
It might look a bit confusing if you're not used to it and it's not too common, but hey, it's an option, when you really want a constructor function that you'll use only once and there's no sense of giving it a name.

JavaScript for...in Loop

The JavaScript for...in statement loops through the properties of an object.

var Employee={fname:"John",lname:"Doe",age:25,salary:10000};
for (x in Employee)
{
alert(x+' : '+Employee[x]);
}

What is a Web service?

Web service is any piece of software that makes itself available over the Internet and uses a standardized XML messaging system. Client invokes a Web service by sending an XML message, then waits for a corresponding XML response. Because all communication is in XML, Web services are not tied to any one operating system or programming language

What UDDI means?

UDDI stands for Universal, Description, Discovery, and Integration. It is the discovery layer in the web services protocol stack.

What is REST?

REST stands for Representational State Transfer

REST vs SOAP

The RESTFul web services are simple to implement and test. It supports various data formats such as XML, JSON etc.

Rest is light weight.

Not just xml, it will support json,html,java script

REST has no WSDL interface definition

REST is over HTTP, but SOAP can be over any transport protocols such HTTP, FTP, STMP, JMS etc.

SOAP is using soap envelope, but REST is just XML.

REST is stateless. REST services are easily cacheable.

REST has the support for sending parameters to the method/resource that gets invoked in the existing query parameters style like
example.com/users/user1/address

WS-Security which adds some enterprise security features in SOAP

Sample WADL

</representation>

</request>

</response>

</method>

</resource>

Service/Provider Class

@Singleton

@Path("officeservice")

public class HRBColsService {

@POST

@Produces(Constants.JSONRESP)

@Consumes(MediaType.APPLICATION_JSON)

@Path("{applicationName}/{templateID}"+Constants.RAW_DATA_URI+"/getOfficeDetailsByAddress/")

public MapResponse getOfficeDetailsByAddress(@PathParam("applicationName") String applicationName,

@PathParam("templateID") String templateID, @FormParam("mreq") String txtRequest){

….

}

@GET

@Produces(Constants.JAVASCRIPTRESP)

@Path("{applicationName}/{templateID}"+Constants.JSONP_URI+"/getOfficeDetailsByQuery/")

public String getOfficeDetailsByQuery(@PathParam("applicationName") String applicationName,

@PathParam("templateID") String templateID,@QueryParam("query") String query,@QueryParam("callback") String callback

) {

return callback+"("+jsonString+");";

}

Web.xml

<display-name>JAX-RS REST Servlet</display-name>

<servlet-name>services</servlet-name>

<servlet-class>

com.sun.jersey.spi.container.servlet.ServletContainer

</servlet-class>

<init-param>

<param-name>com.sun.jersey.config.property.packages</param-name>

<param-value>com.test.services.gmap</param-value>

</init-param>

<load-on-startup>1</load-on-startup>

</servlet>

<servlet-mapping>

<servlet-name>services</servlet-name>

<url-pattern>/*</url-pattern>

</servlet-mapping>

jersey will consider all the classes which are under the package com.test.services.gmap

How to expose one service implementation as Restful and webservice?
Create a normal web application in eclipse and use the below files. I assume you are aware of pom.xml

package com.sudheer.cxf.demo.servImpl;

import javax.ws.rs.Consumes;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;

import org.springframework.util.StringUtils;

import com.example.employeeservice.Employee;
import com.example.employeeservice.EmployeeService;
import com.example.employeeservice.NoSuchEmployeeException;
import com.javatch.cxf.dao.utils.EmployeeUtils;

@Path("/")

public class EmployeeServiceImpl implements EmployeeService{

@GET
@Path("/getemployee/{name}/")
@Produces(value = {"application/json" })
public Employee getEmployeesByName(@PathParam("name") String name)
throws NoSuchEmployeeException {
if(EmployeeUtils.employees.containsKey(name)) {
return EmployeeUtils.employees.get(name);
} else {
throw new NoSuchEmployeeException("Employee " + name + "doesn't exists");
}

}

@POST
@Path("/addemployee/")
@Consumes(value="application/json")
@Produces(value = {"application/json" })
public void addEmployee(Employee employee) {
if(StringUtils.hasText(employee.getName())){
EmployeeUtils.employees.put(employee.getName(), employee);
} else {
System.out.println("Invalid Employee object");
}

}

}

package com.sudheer.test.client;

import java.io.BufferedInputStream;

import java.io.ByteArrayOutputStream;

import java.io.InputStream;

import java.net.MalformedURLException;

import java.net.URL;

public class RestClient {

public static void main(String[] args) {

System.out.println("Sent HTTP GET request to query customer info");

URL url;

try {

url = new URL("http://localhost:8080/cxfpoc/employeeservice/getemployee/Ryan");

getStringFromIOStream(url);

} catch (MalformedURLException e1) {

// TODO Auto-generated catch block

e1.printStackTrace();

}

private static void getStringFromIOStream(URL url) {

try {

InputStream in = url.openStream();

BufferedInputStream bis = new BufferedInputStream(in);

ByteArrayOutputStream buf = new ByteArrayOutputStream();

int result = bis.read();

while(result != -1) {

byte b = (byte)result;

buf.write(b);

result = bis.read();

}

System.out.println(buf.toString());

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

package com.sudheer.test.client;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.example.employeeservice.Employee;

import com.example.employeeservice.EmployeeService;

import com.example.employeeservice.NoSuchEmployeeException;

public class SoapClient {

/**

* @param args

public static void main(String[] args) {

// TODO Auto-generated method stub

ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext(new String[]

{"/client-beans.xml"});

EmployeeService client = (EmployeeService) context.

getBean("orderClient");

// Populate the Order bean

Employee employee;

try {

employee = client.getEmployeesByName("Ryan");

System.out.println("Employee Name : "+employee.getName());

} catch (NoSuchEmployeeException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

client-bean.xml

This will be used in SoapClient java

<?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:jaxws="http://cxf.apache.org/jaxws"

xsi:schemaLocation="

http://www.springframework.org/schema/beans

http://www.springframework.org/schema/beans/spring-beans.xsd

http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd">

<jaxws:client id="orderClient" serviceClass=

"com.example.employeeservice.EmployeeService" address=

"http://localhost:8080/cxfpoc/EmployeeService" />

</beans>

cxfbeans.xml

Used to expose Restful and webservice

<?xml version="1.0" encoding="UTF-8"?>

<!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor

license agreements. See the NOTICE file distributed with this work for additional

information regarding copyright ownership. The ASF licenses this file to

you under the Apache License, Version 2.0 (the "License"); you may not use

this file except in compliance with the License. You may obtain a copy of

the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required

by applicable law or agreed to in writing, software distributed under the

License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS

OF ANY KIND, either express or implied. See the License for the specific

language governing permissions and limitations under the License. -->

<beans xmlns="http://www.springframework.org/schema/beans"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xmlns:aop="http://www.springframework.org/schema/aop"

xmlns:jaxws="http://cxf.apache.org/jaxws"

xmlns:jaxrs="http://cxf.apache.org/jaxrs"

xsi:schemaLocation="

http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd

http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd

http://cxf.apache.org/jaxrs http://cxf.apache.org/schemas/jaxrs.xsd

http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd" >

<jaxrs:server id="EmployeeServiceRS" address="/employeeservice" >

<jaxrs:serviceBeans>

</jaxrs:serviceBeans>

<jaxrs:providers>

</jaxrs:providers>

</jaxrs:server>

<jaxws:endpoint id="EmployeeService"

implementor="#employeeServicesRS" address="/EmployeeService" />

<aop:config>

<aop:aspect ref="beforeAndAfterLogging">

<aop:pointcut expression="within(com.hrblock.cxf.demo.servImpl.*)" id="before-method" />

<aop:before method="beforeMethod" pointcut-ref="before-method" />

</aop:aspect>

<aop:aspect ref="beforeAndAfterLogging">

<aop:pointcut expression="within(com.hrblock.cxf.demo.servImpl.*)" id="after-method" />

<aop:after method="afterMethod" pointcut-ref="after-method" />

</aop:aspect>

</aop:config>

</bean>

</beans>

web.xml

<!DOCTYPE web-app PUBLIC

"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"

"http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>

<display-name>Archetype Created Web Application</display-name>

<context-param>

<param-name>contextConfigLocation</param-name>

<param-value>WEB-INF/cxfbeans.xml</param-value>

</context-param>

<listener-class>

org.springframework.web.context.ContextLoaderListener

</listener-class>

</listener>

<servlet-name>CXFServlet</servlet-name>

<display-name>CXF Servlet</display-name>

<servlet-class>

org.apache.cxf.transport.servlet.CXFServlet

</servlet-class>

<load-on-startup>1</load-on-startup>

</servlet>

<servlet-mapping>

<servlet-name>CXFServlet</servlet-name>

<url-pattern>/*</url-pattern>

</servlet-mapping>

</web-app>

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">

<groupId>com.javatch.cxf</groupId>

<artifactId>cxfpoc</artifactId>

<name>com.javatch.cxf Maven Webapp</name>

<url>http://maven.apache.org</url>

<cxf.version>2.5.1</cxf.version>

</properties>

<groupId>junit</groupId>

<artifactId>junit</artifactId>

</dependency>

<groupId>org.apache.cxf</groupId>

<artifactId>cxf-rt-frontend-jaxws</artifactId>

<version>${cxf.version}</version>

</dependency>

<groupId>org.apache.cxf</groupId>

<artifactId>cxf-rt-frontend-jaxrs</artifactId>

<version>${cxf.version}</version>

</dependency>

<groupId>aspectj</groupId>

<artifactId>aspectjrt</artifactId>

</dependency>

<groupId>org.aspectj</groupId>

<artifactId>aspectjweaver</artifactId>

</dependency>

<groupId>org.codehaus.jackson</groupId>

<artifactId>jackson-jaxrs</artifactId>

</dependency>

</dependencies>

<build>

<defaultGoal>install</defaultGoal>

<directory>src/main/resources/wsdl</directory>

</resource>

<directory>src/main/resources</directory>

</resource>

</resources>

<artifactId>maven-war-plugin</artifactId>

<directory>src/main/resources/wsdl</directory>

</includes>

</resource>

<directory>src/main/resources</directory>

</includes>

</resource>

</webResources>

</configuration>

</plugin>

<artifactId>maven-compiler-plugin</artifactId>

</configuration>

</plugin>

</plugins>

</pluginManagement>

<groupId>org.apache.cxf</groupId>

<artifactId>cxf-codegen-plugin</artifactId>

<version>${cxf.version}</version>

<id>generate-sources</id>

<phase>generate-sources</phase>

<sourceRoot>${basedir}/target/generated/cxf</sourceRoot>

<wsdl>src/main/resources/wsdl/EmployeeService.wsdl</wsdl>

<!-- <bindingFiles> <bindingFile>${basedir}/wsdl/binding.xml</bindingFile>

</bindingFiles> -->

</wsdlOption>

</wsdlOptions>

</configuration>

<goals>

</goals>

</execution>

</executions>

</plugin>

</plugins>

</build>

</project>

Service listings and WADL queries

Links to WADL instances for RESTful endpoints are available from {base endpointaddress}/services, in addition to SOAP endpoints if any.
Base address : 'http://localhost:8080'
WAR name : 'restpoc'
CXFServlet : '/books/*'
jaxrs:server/@address = '/getemployee'
and visiting

http://localhost:8080/restpoc/books
http://localhost:8080/restpoc/books/services

will let you see all the WADL links.

Going to the service listings page is not the only way to see WADL instances, one can also get it using a ?_wadl query.

http://localhost:8080/restpoc/books/getemployee?_wadl

will give you the description of all the root resource classes registered
with a given jaxrs:server endpoint.

For example, if the following 2 root resource classes has been registered with this endpoint:

@Path("/fiction")
public class FictionBookgetemployee {
}
@Path("/sport")
public class SportBookgetemployee {
}
then WADL will contain the description of both FictionBookgetemployee and SportBookgetemployee resources.

> http://localhost:8080/restpoc/books/getemployee/fiction?_wadl
> http://localhost:8080/restpoc/books/getemployee/sport?_wadl

Service listings and WADL queries - Jersey

To get the WADL from Jersey

WAR NAME - Jersey-Sample
Jersey Servlet Mapping - /*

http://localhost:8080/Jersey-Sample/application.wadl

Use this URL to call the below service
http://localhost:8080/Jersey-Sample/getemployee/sdheer/32

@Path("/")
public class EmployeeServiceImpl{

@Path("/getemployee/{name}/{name}")
@Produces(value = {"application/json" })
public Employee getEmployeesByName(@PathParam("name") String name,@PathParam("age") int age)

Use this URL to call the below service

@Path("/")
public class EmployeeServiceImpl{
http://localhost:8080/Jersey-Sample/
@GET
@Produces(value = {"application/json" })
public Employee getEmployeesByName()

You cannot have two different services like below without proper path

@GET
@Produces(value = {"application/json" })
public Employee getEmployeesByName(){
}

@GET
@Produces(value = {"application/json" })
public Employee anotherMethod(){
}

Error, A message body writer for Java type, class com.jersey.demo.beans.Employee, and MIME media type, application/json, was not found

Add @XmlRootElement top of the bean class Employee

A Complete Simple Jersey Rest Service Example

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>Jersey Sample</display-name>

<servlet>
<display-name>JAX-RS REST Servlet</display-name>
<servlet-name>services</servlet-name>
<servlet-class>
com.sun.jersey.spi.container.servlet.ServletContainer
</servlet-class>
<init-param>
<param-name>com.sun.jersey.config.property.packages</param-name>
<param-value>com.jersey.demo.servImpl</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>services</servlet-name>
<url-pattern>/*</url-pattern>
</servlet-mapping>
</web-app>

package com.jersey.demo.servImpl;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;

import com.jersey.demo.beans.Employee;

@Path("/")

public class EmployeeServiceImpl{

@GET
@Path("/getemployee/{name}/{name}")
@Produces(value = {"application/json" })
public Employee getEmployeesByName(){
Employee employee = new Employee();
employee.setName("name");
employee.setAge(123);
return employee;
}
}

package com.jersey.demo.beans;

import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class Employee {

private String name;
private int age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}

Java

Tuesday, March 5, 2013

Java Script

Monday, February 18, 2013

XMLBeans

Thursday, December 13, 2012

Restful Service