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maven April 8, 2010 2 min read by mkyong 20 comments

Maven dependency libraries not deploy in Eclipse IDE

Problem By default, while starting the Tomcat server instance in Eclipse, the project’s dependency libraries will not deploy to the Eclipse’s Tomcat plugin library folder ‘WEB-INF/lib’ correctly. See this “.classpath” file, that is generated by Maven “mvn eclipse:eclipse” command. <classpath> <classpathentry kind="src" path="src/main/java" including="**/*.java"/> <classpathentry kind="src" path="src/main/resources" excluding="**/*.java"/> <classpathentry kind="output" path="target/classes"/> <classpathentry kind="var" path="M2_REPO/org/apache/struts/struts-core/1.3.10/struts-core-1.3.10.jar" /> […]

hibernate April 8, 2010 4 min read by mkyong 57 comments

Hibernate – save image into database

To save an image into database, you need to define a table column as blob data type in MySQL, or equivalent binary type in others database. In Hibernate side, you can declare a byte array variable to store the image data. Download this example – Hibernate-Image-Example.zip Here’s an Maven project to use Hibernate to save […]

java April 7, 2010 2 min read by mkyong 8 comments

Java – How to save byte[] to a file

This article shows a few ways to save a byte[] into a file. For JDK 1.7 and above, the NIO Files.write is the simplest solution to save byte[] to a file. // bytes = byte[] Path path = Paths.get("/path/file"); Files.write(path, bytes); FileOutputStream is the best alternative. try (FileOutputStream fos = new FileOutputStream("/path/file")) { fos.write(bytes); //fos.close […]

tutorials April 7, 2010 2 min read by mkyong 12 comments

Java Regular Expression Tutorial

Java Regular Expression Tutorials with full example and unit test, common regular expression example like username, password, url, file extension, date, time email , hex color code and etc

java April 6, 2010 3 min read by mkyong 9 comments

Java – How to convert File to byte[]

In Java, we can use Files.readAllBytes(path) to convert a File object into a byte[]. import java.nio.file.Files; import java.nio.file.Path; import java.nio.file.Paths; String filePath = "/path/to/file"; // file to byte[], Path byte[] bytes = Files.readAllBytes(Paths.get(filePath)); // file to byte[], File -> Path File file = new File(filePath); byte[] bytes = Files.readAllBytes(file.toPath()); P.S The NIO Files class is […]

spring April 5, 2010 5 min read by mkyong 112 comments

Spring 3 + Quartz 1.8.6 scheduler example

Updated on 25 July 2012 – Upgrade article to use Spring 3 and Quartz 1.8.6 (it was Spring 2.5.6 and Quartz 1.6) In this tutorial, we will show you how to integrate Spring with Quartz scheduler framework. Spring comes with many handy classes to support Quartz, and decouple your class to Quartz APIs. Tools Used […]

spring April 4, 2010 5 min read by mkyong 38 comments

Spring AOP transaction management in Hibernate

Transaction management is required to ensure the data integrity and consistency in database. Spring’s AOP technique is allow developers to manage the transaction declarative. Here’s an example to show how to manage the Hibernate transaction with Spring AOP. P.S Many Hibernate and Spring configuration files are hidden, only some important files are shown, if you […]

java April 3, 2010 3 min read by mkyong 58 comments

Quartz 1.6 scheduler tutorial

Quartz is a powerful and advance scheduler framework, to help Java developer to scheduler a job to run at a specified date and time. This tutorial show you how to develop a scheduler job using Quartz 1.6.3. Note This example is a bit outdate, unless you are still using the old Quartz 1.6.3 library, otherwise, […]

java April 3, 2010 5 min read by mkyong 2 comments

How to modify XML file in Java – (JDOM)

This tutorial shows how to use the JDOM to modify an XML file. Table of contents 1. Download the JDOM 2.x 2. The XML file, before and after 3. Modify XML file 4. Find and remove XML elements 5. Download Source Code 6. References P.S Tested with JDOM 2.0.6 Note We need to understand how […]

tutorials April 2, 2010 2 min read by mkyong 0 comments

Java XML Tutorial

Java XML Tutorials with full example, including how to read, write and modify the xml file with DOM, SAX and JDOM parsers. And also how to convert object to / from XML via JAXB.

spring April 2, 2010 2 min read by mkyong 14 comments

Spring + JDK Timer scheduler example

Note Learn the JDK Timer scheduler example without Spring and compare the different with this example. In this example, you will use Spring’s Scheduler API to schedule a task. 1. Scheduler Task Create a scheduler task… package com.mkyong.common; public class RunMeTask { public void printMe() { System.out.println("Run Me ~"); } } <bean id="runMeTask" class="com.mkyong.common.RunMeTask" /> […]

java April 2, 2010 5 min read by mkyong 8 comments

How to write XML file in Java – (DOM Parser)

This tutorial shows how to use the Java built-in DOM APIs to write data to an XML file. Table of contents 1. Write XML to a file 2. Pretty Print XML 3. Write XML elements, attributes, comments CDATA, etc 4. DOM FAQs 4.1 How to disable the XML declaration? 4.2 How to change the XML […]

tutorials April 1, 2010 1 min read by mkyong 17 comments

TestNG Tutorial

TestNG tutorial with full example, introduce the TestNG basic usage, annotation support, and test case for expected exception test, ignore test, time test, suite test, parameterized test, dependency test and etc

tutorials April 1, 2010 1 min read by mkyong 28 comments

JUnit Tutorial

JUnit tutorial with full example, introduce the JUnit basic usage, annotation support, and test case for expected exception test, ignore test, time test, suite test, parameterized test and etc

tutorials April 1, 2010 8 min read by mkyong 132 comments

Spring Tutorial

Spring tutorial with full example, including Spring’s basic usage, bean configuration, dependency injection, AOP, integration with JDBC, Hibernate , Struts, Quartz, E-mail and etc

java April 1, 2010 1 min read by mkyong 6 comments

JDK Timer scheduler example

JDK Timer is a simple scheduler for a specified task for repeated fixed-delay execution. To use this, you have to extends the TimerTask abstract class, override the run() method with your scheduler function. RunMeTask.java package com.mkyong.common; import java.util.TimerTask; public class RunMeTask extends TimerTask { @Override public void run() { System.out.println("Run Me ~"); } } Now, […]

spring March 31, 2010 10 min read by mkyong 149 comments

Maven + (Spring + Hibernate) Annotation + MySql Example

Download It – Spring-Hibernate-Annotation-Example.zip In last tutorial, you use Maven to create a simple Java project structure, and demonstrate how to use Hibernate in Spring framework to do the data manipulation works(insert, select, update and delete) in MySQL database. In this tutorial, you will learn how to do the same thing in Spring and Hibernate […]

tutorials March 31, 2010 1 min read by mkyong 67 comments

Apache Maven Tutorial

Apache Maven Tutorial – A series of simple and quick Maven examples.

tutorials March 31, 2010 6 min read by mkyong 123 comments

Hibernate Tutorial

Hibernate tutorial with full example, including Hibernate configuration, association relationship, HQL, criteria, transaction, tips, performance, integration with Spring, Struts and etc

spring March 31, 2010 3 min read by mkyong 6 comments

Spring Resource loader with getResource() example

Spring’s resource loader provides a very generic getResource() method to get the resources like (text file, media file, image file…) from file system , classpath or URL. You can get the getResource() method from the application context. Here’s an example to show how to use getResource() to load a text file from 1. File system […]

spring March 31, 2010 3 min read by mkyong 27 comments

Spring – Sending e-mail with attachment

Here’s an example to use Spring to send e-mail that has attachments via Gmail SMTP server. In order to contains the attachment in your e-mail, you have to use Spring’s JavaMailSender & MimeMessage , instead of MailSender & SimpleMailMessage. 1. Project dependency Add the JavaMail and Spring’s dependency. File : 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 […]

spring March 30, 2010 3 min read by mkyong 2 comments

Spring – Define an E-mail template in bean configuration file

In last Spring’s email tutorial, you hard-code all the email properties and message content in the method body, it’s not practical and should be avoid. You should consider define the email message template in the Spring’s bean configuration file. 1. Project dependency Add the JavaMail and Spring’s dependency. File : 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 […]

spring March 30, 2010 2 min read by mkyong 22 comments

Spring PropertyPlaceholderConfigurer example

Often times, most Spring developers just put the entire deployment details (database details, log file path) in XML bean configuration file as following : <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="customerDAO" class="com.mkyong.customer.dao.impl.JdbcCustomerDAO"> <property name="dataSource" ref="dataSource" /> </bean> <bean id="customerSimpleDAO" class="com.mkyong.customer.dao.impl.SimpleJdbcCustomerDAO"> <property name="dataSource" ref="dataSource" /> </bean> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="com.mysql.jdbc.Driver" /> <property name="url" value="jdbc:mysql://localhost:3306/mkyongjava" […]

spring March 29, 2010 3 min read by mkyong 58 comments

Spring – Sending E-mail via Gmail SMTP server with MailSender

Spring comes with a useful ‘org.springframework.mail.javamail.JavaMailSenderImpl‘ class to simplify the e-mail sending process via JavaMail API. Here’s a Maven build project to use Spring’s ‘JavaMailSenderImpl‘ to send an email via Gmail SMTP server. 1. Project dependency Add the JavaMail and Spring’s dependency. File : 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"> <modelVersion>4.0.0</modelVersion> <groupId>com.mkyong.common</groupId> <artifactId>SpringExample</artifactId> <packaging>jar</packaging> <version>1.0-SNAPSHOT</version> […]

spring March 29, 2010 3 min read by mkyong 10 comments

Spring @PostConstruct and @PreDestroy example

In Spring, you can either implements InitializingBean and DisposableBean interface or specify the init-method and destroy-method in bean configuration file for the initialization and destruction callback function. In this article, we show you how to use annotation @PostConstruct and @PreDestroy to do the same thing. Note The @PostConstruct and @PreDestroy annotation are not belong to […]

java March 28, 2010 3 min read by mkyong 463 comments

JavaMail API – Sending email via Gmail SMTP example

In this article, we will show you how to send an email via Gmail SMTP server. To send email in Java, we need JavaMail pom.xml <dependency> <groupId>com.sun.mail</groupId> <artifactId>javax.mail</artifactId> <version>1.6.2</version> </dependency> 1. Gmail SMTP via TLS SMTP = smtp.gmail.com Port = 587 SendEmailTLS.java package com.mkyong; import javax.mail.*; import javax.mail.internet.InternetAddress; import javax.mail.internet.MimeMessage; import java.util.Properties; public class SendEmailTLS […]

spring March 28, 2010 3 min read by mkyong 6 comments

Spring Auto proxy creator example

In last Spring AOP examples – advice, pointcut and advisor, you have to manually create a proxy bean (ProxyFactoryBean) for each beans whose need AOP support. This is not an efficient way, for example, if you want all of your DAO classes in customer module to implement the AOP feature with SQL logging support (advise), […]

spring March 28, 2010 2 min read by mkyong 8 comments

Spring init-method and destroy-method example

In Spring, you can use init-method and destroy-method as attribute in bean configuration file for bean to perform certain actions upon initialization and destruction. Alternative to InitializingBean and DisposableBean interface. Example Here’s an example to show you how to use init-method and destroy-method. package com.mkyong.customer.services; public class CustomerService { String message; public String getMessage() { […]

spring March 27, 2010 2 min read by mkyong 15 comments

Spring InitializingBean and DisposableBean example

In Spring, InitializingBean and DisposableBean are two marker interfaces, a useful way for Spring to perform certain actions upon bean initialization and destruction. For bean implemented InitializingBean, it will run afterPropertiesSet() after all bean properties have been set. For bean implemented DisposableBean, it will run destroy() after Spring container is released the bean. Example Here’s […]

maven March 26, 2010 1 min read by mkyong 3 comments

Maven – How to download JavaMail API

JavaMail is now available in Maven Central repository. pom.xml <dependency> <groupId>com.sun.mail</groupId> <artifactId>javax.mail</artifactId> <version>1.6.2</version> </dependency> If you want to use the core JavaMail API to send email, you have to get the JavaMail library – mail.jar and activation.jar. Unfortunately, those libraries are not available in the Maven central repository, you have to download it from java.Net […]

spring March 26, 2010 3 min read by mkyong 32 comments

Spring bean scopes example

In Spring, bean scope is used to decide which type of bean instance should be return from Spring container back to the caller. 5 types of bean scopes supported : singleton – Return a single bean instance per Spring IoC container prototype – Return a new bean instance each time when requested request – Return […]

spring March 26, 2010 6 min read by mkyong 39 comments

Spring AOP Example – Pointcut , Advisor

In last Spring AOP advice examples, the entire methods of a class are intercepted automatically. But for most cases, you may just need a way to intercept only one or two methods, this is what ‘Pointcut’ come for. It allow you to intercept a method by it’s method name. In addition, a ‘Pointcut’ must be […]

spring March 25, 2010 9 min read by mkyong 122 comments

Spring AOP Example – Advice

Spring AOP + AspectJ Using AspectJ is more flexible and powerful, please refer to this tutorial – Using AspectJ annotation in Spring AOP. Spring AOP (Aspect-oriented programming) framework is used to modularize cross-cutting concerns in aspects. Put it simple, it’s just an interceptor to intercept some processes, for example, when a method is execute, Spring […]

spring March 25, 2010 2 min read by mkyong 5 comments

Spring Filter components in auto scanning

In this Spring auto component scanning tutorial, you learn about how to make Spring auto scan your components. In this article, we show you how to do component filter in auto scanning process. 1. Filter component – include See following example to use Spring “filtering” to scan and register components’ name which matched defined “regex”, […]

spring March 24, 2010 6 min read by mkyong 59 comments

Spring Auto scanning components

Normally you declare all the beans or components in XML bean configuration file, so that Spring container can detect and register your beans or components. Actually, Spring is able to auto scan, detect and instantiate your beans from pre-defined project package, no more tedious beans declaration in in XML file. Following is a simple Spring […]

spring March 23, 2010 9 min read by mkyong 202 comments

Maven + Spring + Hibernate + MySql Example

This example will use Maven to create a simple Java project structure, and demonstrate how to use Hibernate in Spring framework to do the data manipulation works(insert, select, update and delete) in MySQL database. Final project structure Your final project file structure should look exactly like following, if you get lost in the folder structure […]

spring March 23, 2010 2 min read by mkyong 10 comments

Spring Named Parameters examples in SimpleJdbcTemplate

In JdbcTemplate, SQL parameters are represented by a special placeholder “?” symbol and bind it by position. The problem is whenever the order of parameter is changed, you have to change the parameters bindings as well, it’s error prone and cumbersome to maintain it. To fix it, you can use “Named Parameter“, whereas SQL parameters […]

spring March 22, 2010 3 min read by mkyong 6 comments

Spring SimpleJdbcTemplate Querying examples

Here are few examples to show how to use SimpleJdbcTemplate query() methods to query or extract data from database. In JdbcTemplate query(), you need to manually cast the returned result to desire object type, and pass an Object array as parameters. In SimpleJdbcTemplate, it is more user friendly and simple. jdbctemplate vesus simplejdbctemplate Please compare […]

spring March 21, 2010 2 min read by mkyong 2 comments

Spring SimpleJdbcTemplate batchUpdate() example

In this tutorial, we show you how to use batchUpdate() in SimpleJdbcTemplate class. See batchUpdate() example in SimpleJdbcTemplate class. //insert batch example public void insertBatch(final List<Customer> customers){ String sql = "INSERT INTO CUSTOMER " + "(CUST_ID, NAME, AGE) VALUES (?, ?, ?)"; List<Object[]> parameters = new ArrayList<Object[]>(); for (Customer cust : customers) { parameters.add(new Object[] […]

spring March 20, 2010 6 min read by mkyong 40 comments

Spring JdbcTemplate Querying Examples

Here are a few examples to show you how to use Spring JdbcTemplate to query or extract data from database. Technologies used : Spring Boot 2.1.2.RELEASE Spring JDBC 5.1.4.RELEASE Maven 3 Java 8 In Short: jdbcTemplate.queryForObject for single row or value jdbcTemplate.query for multiple rows or list Note The article is updated from Spring core […]