Spring - Sending E-Mail with MailSender

Spring - Sending E-Mail with MailSender

Spring  

Sending email using Spring "org.springframework.mail.javamail.JavaMailSenderImpl" class simplifies the process with JavaMail API. Below example will give step by step to send email by using Gmail SMTP server configurations.

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/xsd/maven-4.0.0.xsd">
 <modelVersion>4.0.0</modelVersion>
 <groupId>org.springframework.samples</groupId>
 <artifactId>SendingEmail</artifactId>
 <version>0.0.1-SNAPSHOT</version>

 <dependencies>

  <!-- Spring framework -->
  <dependency>
   <groupId>org.springframework</groupId>
   <artifactId>spring</artifactId>
   <version>2.5.6.SEC03</version>
  </dependency> 

  <!-- Java Mail API -->
  <dependency>
   <groupId>javax.mail</groupId>
   <artifactId>mail</artifactId>
   <version>1.4.3</version>
  </dependency>

 </dependencies>
</project>

email.xml

<beans xmlns="http://www.springframework.org/schema/beans"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

 <bean id="emailSender" class="org.springframework.mail.javamail.JavaMailSenderImpl">
  <property name="host" value="smtp.gmail.com" />
  <property name="port" value="587" />
  <property name="username" value="USERNAME" />
  <property name="password" value="PASSWORD" />

  <property name="javaMailProperties">
   <props>
    <prop key="mail.smtp.auth">true</prop>
    <prop key="mail.smtp.starttls.enable">true</prop>
   </props>
  </property>
 </bean>

 <bean id="emailBean" class="com.app.email.Mailer">
  <property name="emailSender" ref="emailSender" />
 </bean>

</beans>

Mailer.java

package com.app.email;

import org.springframework.mail.MailSender;
import org.springframework.mail.SimpleMailMessage;

public class Mailer {

 private MailSender emailSender;
 
 //Setter for emailSender
 public void setEmailSender(MailSender emailSender) {
  this.emailSender = emailSender;
 }
 
 //Method to send email
 public void sendMail(String from, String to, String subject, String msg) {

  SimpleMailMessage simpleMsg = new SimpleMailMessage();
  
  simpleMsg.setFrom(from);
  simpleMsg.setTo(to);
  simpleMsg.setSubject(subject);
  simpleMsg.setText(msg);
  
  //Finally sending email using MailSender
  emailSender.send(simpleMsg); 
 }
}

SendEmail.java

package com.app.email;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class SendEmail {

 public static void main(String[] args) {

  String from = "from@gmail.com";
  String to = "to@gmail.com";
  String subject = "Hello World !";
  String msg = "Hello World, How are you ???";

  ApplicationContext context = new ClassPathXmlApplicationContext("email.xml");

  try {
   Mailer mailer = (Mailer) context.getBean("emailBean");
   mailer.sendMail(from, to, subject, msg);

  } catch (Exception e) {
   e.printStackTrace();
  }
 }
}

Spring + @PropertySource with @Value and Environment

Spring + @PropertySource with @Value and Environment

Spring  

In Spring we can configure our application properties in property file and by @PropertySource annotation we can configure externalized configuration file. Those property values can be read by using @Value annotation or by using Environment class.
In below lets see simple example how to use @PropertySource to read property file and to fetch those values using @Value and Environment class. Simple example that we need to serve static resources from different locations to configure in Spring and that too separate location for images and separate for text files etc., Those locations are configured in "myConfig.properties" file.

myConfig.properties

staticresourceloader.imageFileLocation.path:file:C:\\images\\

staticresourceloader.txtFileLocation.path:file:C:\\txtfiles\\

Reading values using @Value annotation

package com.app.staticresourceloader;


import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.PropertySource;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@ComponentScan
@EnableAutoConfiguration
@PropertySource("classpath:myConfig.properties")
@SpringBootApplication
public class Application extends WebMvcConfigurerAdapter  {

 @Value("${staticresourceloader.imageFileLocation.path}")
    private String staticImageFilePath;
 
 @Value("${staticresourceloader.txtFileLocation.path}")
    private String staticTxtFilePath;
 
 public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
        
    }
    
 @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        
  System.out.println("IMAGE FILE PATH :::: "+staticImageFilePath);
  System.out.println("TEXT FILE PATH  :::: "+staticTxtFilePath);
  
  registry.addResourceHandler("/api/image/**").addResourceLocations(staticImageFilePath);
        registry.addResourceHandler("/api/txt/**").addResourceLocations(staticTxtFilePath);
        
    }   
}

Reading values using Environment

package com.app.staticresourceloader;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.env.Environment;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@ComponentScan
@EnableAutoConfiguration
@PropertySource("classpath:myConfig.properties")
@SpringBootApplication
public class Application extends WebMvcConfigurerAdapter  {

 @Autowired
 private Environment pathDetails;
 
 public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
        
    }
    
 @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
  
  String imagePath = pathDetails.getProperty("staticresourceloader.imageFileLocation.path");
  String txtPath = pathDetails.getProperty("staticresourceloader.txtFileLocation.path");
  
  System.out.println("IMAGE FILE PATH :::: "+imagePath);
  System.out.println("TEXT FILE PATH  :::: "+txtPath);
  
  registry.addResourceHandler("/api/image/**").addResourceLocations(imagePath);
        registry.addResourceHandler("/api/txt/**").addResourceLocations(txtPath);
        
    }   
}

OUTPUT:

Spring Boot + Spring Security + Serve static resources from different locations

Spring Boot + Spring Security + Serve static resources from different locations

Spring Security  

In Spring we can configure static resources such as  images, js, and, css files from specific locations under web application root, the classpath, and other locations. Even we can configure multiple locations to server different type of file.
An implementation of WebMvcConfigurer interface in WebMvcConfigurerAdapter abstract class with empty methods allowing sub-classes to override only the methods they're interested in. To achieve and serve static resources from different locations we need to extend WebMvcConfigurerAdapter class and need to @Override addResourceHandlers() method in our Application class.
Lets simple example to serve static resources like images and text files from different locations.
Here in this example we are loading images and text files from different locations like

• images from C://images 
• text files from C://txtfiles

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<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/xsd/maven-4.0.0.xsd">
 <modelVersion>4.0.0</modelVersion>

 <groupId>com.app</groupId>
 <artifactId>staticresourceloader</artifactId>
 <version>0.0.1-SNAPSHOT</version>
 <packaging>war</packaging>

 <name>staticresourceloader</name>
 <description>staticresourceloader project</description>

 <parent>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-parent</artifactId>
  <version>1.2.5.RELEASE</version>
  <relativePath/> <!-- lookup parent from repository -->
 </parent>

  <dependencies>
  
  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-security</artifactId>
  </dependency>
  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-web</artifactId>
  </dependency>
  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-ws</artifactId>
  </dependency>
  
  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-tomcat</artifactId>
   <scope>provided</scope>
  </dependency>
  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-test</artifactId>
   <scope>test</scope>
  </dependency>
 </dependencies>
 
 <build>
  <plugins>
   <plugin>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-maven-plugin</artifactId>
   </plugin>
  </plugins>
 </build>

</project>

application.properties

security.user.password=Efhj34tGVW

staticresourceloader.imageFileLocation.path:file:C:\\images\\

staticresourceloader.txtFileLocation.path:file:C:\\txtfiles\\

Application.java

package com.app.staticresourceloader;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@ComponentScan
@EnableAutoConfiguration
@SpringBootApplication
public class Application extends WebMvcConfigurerAdapter  {

 @Value("${staticresourceloader.imageFileLocation.path}")
    private String staticImageFilePath;
 
 @Value("${staticresourceloader.txtFileLocation.path}")
    private String staticTxtFilePath;
 
 public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
    
 @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("/api/image/**").addResourceLocations(staticImageFilePath);
        registry.addResourceHandler("/api/txt/**").addResourceLocations(staticTxtFilePath);
    }    
}

ServletInitializer.java

package com.app.staticresourceloader;

import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.context.web.SpringBootServletInitializer;

public class ServletInitializer extends SpringBootServletInitializer {

 @Override
 protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
  return application.sources(Application.class);
 } 
}

MyController.java

package com.app.staticresourceloader;

import java.io.File;
import java.util.ArrayList;
import java.util.Collection;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;


@Controller
public class MyController {

 @Value("${staticresourceloader.imageFileLocation.path}")
    private String staticImageFilePath;
 
 @Value("${staticresourceloader.txtFileLocation.path}")
    private String staticTxtFilePath;
 
 
 @RequestMapping(value="/api/getImageList", method=RequestMethod.GET, headers="Accept=application/json")
 public ResponseEntity<Collection<String>> getImageList(){
  
  Collection<String> fileList = fileList(staticImageFilePath, "image");
  
  return new ResponseEntity<Collection<String>>(fileList, HttpStatus.OK);
 } 
 
 

        @RequestMapping(value="/api/getTxtList", method=RequestMethod.GET, headers="Accept=application/json")
 public ResponseEntity<Collection<String>> getTxtFileList(){
  
  Collection<String> fileList = fileList(staticTxtFilePath, "txt");
  
  return new ResponseEntity<Collection<String>>(fileList, HttpStatus.OK);
 } 
 
 

        public Collection<String> fileList(String folderPath, String type) {
  
  File directory = new File(folderPath.replace("file:", ""));
  File[] fList = directory.listFiles();
  
  Collection<String> list = new ArrayList<String>();
  
  for (File file : fList) {
   
   list.add("http://localhost:8080/api/"+type+"/"+file.getName());
  }  
  return list;
 } 
}

OUTPUT:

Spring Resource Loader with example

Spring Resource Loader with example

Spring Resource Loader  

Spring Resource Loader is very generic and easy to load resources directly as file, url or classpath and of any file types like text, media or image. By using getResource() we can implement single generic method for any file type. By implementing ResourceLoaderAware interface we can inject ResourceLoader object into the bean, since ResourceLoader is non-accessable from application context.

ResourceBeanConfig.xml

<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

   <bean id="resource" class="com.app.javadiscover.ResourceBean" />
   
</beans>

ResourceBean.java

package com.app.javadiscover;

import org.springframework.context.ResourceLoaderAware;
import org.springframework.core.io.Resource;
import org.springframework.core.io.ResourceLoader;

public class ResourceBean implements ResourceLoaderAware {
 private ResourceLoader resourceLoader;
 
 public void setResourceLoader(ResourceLoader resourceLoader) {
  this.resourceLoader = resourceLoader;
 }
  
 public Resource getResource(String location){
  return resourceLoader.getResource(location);
 }
}

LoadResource.java

package com.app.javadiscover;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.core.io.Resource;


public class LoadResource  {

 public static void main( String[] args )
    {
     ApplicationContext appContext =  new ClassPathXmlApplicationContext("ResourceBeanConfig.xml");

     Resource resource = appContext.getResource("classpath:ResourceBeanConfig.xml");
     
    try{
        InputStream iStream = resource.getInputStream();
          BufferedReader bReader = new BufferedReader(new InputStreamReader(iStream));
         
          String text;
          
          while ((text = bReader.readLine()) != null) {
             System.out.println(text);
          } 
          bReader.close();
         
     }catch(IOException e){
      e.printStackTrace();
     }
     
    }
}

OUTPUT:

In above example we have used classpath to load xml file and to print line by line. Similar way we can use file and url resource loader as like below.


     Resource resource = appContext.getResource("file:C:\\javadiscover.xml");

     Resource resource = appContext.getResource("url:http://textfiles.com");

Spring Boot + Restful Web Service + Spring Security

Spring Boot + Restful Web Service + Spring Security

Spring Boot  

When we talk about Spring Boot (Simplifying Spring for Everyone) makes it easy to create stand-alone, production-grade Spring based Applications that you can "just run". Embed Tomcat, Jetty or Undertow directly (no need to deploy WAR files). Now lets see simple example with combination of Spring Boot and Spring Restful Web Service which includes spring security for all our services or API's.

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<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/xsd/maven-4.0.0.xsd">
 <modelVersion>4.0.0</modelVersion>

 <groupId>com.app.javadiscover</groupId>
 <artifactId>springbootdemo</artifactId>
 <version>0.0.1-SNAPSHOT</version>
 <packaging>war</packaging>

 <name>springbootdemo</name>
 <description>Demo project for Spring Boot</description>

 <parent>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-parent</artifactId>
  <version>1.2.5.RELEASE</version>
  <relativePath/> <!-- lookup parent from repository -->
 </parent>

 <properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  <java.version>1.7</java.version>
 </properties>

 <dependencies>
  
  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-security</artifactId>
  </dependency>
  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-web</artifactId>
  </dependency>
  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-ws</artifactId>
  </dependency>
  
  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-tomcat</artifactId>
   <scope>provided</scope>
  </dependency>
  <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-test</artifactId>
   <scope>test</scope>
  </dependency>
 </dependencies>
 
 <build>
  <plugins>
   <plugin>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-maven-plugin</artifactId>
   </plugin>
  </plugins>
 </build>

</project>

ServletInitializer.java

package com.app.javadiscover;

import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.context.web.SpringBootServletInitializer;

public class ServletInitializer extends SpringBootServletInitializer {

 @Override
 protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
  return application.sources(SpringbootdemoApplication.class);
 }
}

SpringbootdemoApplication.java

package com.app.javadiscover;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringbootdemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringbootdemoApplication.class, args);
    }
}

MyController.java

package com.app.javadiscover.controller;

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;


@Controller
public class MyController {

 @RequestMapping(value="/sayhello/{name}", method=RequestMethod.GET, headers="Accept=application/json")
 public ResponseEntity<String> helloController(@PathVariable String name){
  
  String sayHello = "Hello "+name + " :)";
  
  return new ResponseEntity<String>(sayHello, HttpStatus.OK);
 } 
}

application.properties

security.user.password=springsecuritypassword

OUTPUT:

Please download complete project from this link.

Spring: Data access using JdbcDaoSupport

Spring: Data access using JdbcDaoSupport

Spring Data Access  

Similar to JDBCTemplate by extending JdbcDaoSupport classes we can achieve JBDC dataaccess and just need to inject data source into EmpDaoImpl Objects through configuration file. Rest will be taken care by Spring.

In our earlier tutorials we have seen about Spring JDBC and JDBCTemplate examples. Lets take same example class and will extend JdbcDaoSupport class.

pom.xml remains same

Employee.java remains same

EmpDao.java remains same

MyTestClass.java

package com.app;

import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.app.dao.EmpDao;
import com.app.model.Employee;

public class MyTestClass {

 public static void main(String[] args) {
  
  ClassPathXmlApplicationContext appContext = new ClassPathXmlApplicationContext("spring-jdbc.xml");

  EmpDao object = appContext.getBean(EmpDao.class);
  
  Employee emp = new Employee(143, "Bill", "Director");
  
  object.insert(emp);
  
  appContext.close();
 }
}

EmpDaoImpl.java

package com.app.dao;


import org.springframework.jdbc.core.support.JdbcDaoSupport;

import com.app.model.Employee;

public class EmpDaoImpl extends JdbcDaoSupport implements EmpDao {

 public void insert(Employee emp) {
  
  String query = "INSERT INTO employee (id, empname, designation) VALUES (?, ?, ?)";
  
  getJdbcTemplate().update(query, new Object[] { emp.getId(), emp.getEmpName(), emp.getDesignation() });
 }
}

OUTPUT: