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How to install springsource tool suite on linux

Download the STS self-extracting shell script (*.sh) that matches your OS and machine architecture from the following Url: http://www.springsource.org/eclipse-downloads Please make sure to download and install STS versions that match your JDK installation. Once downloaded, launch the installation by running the following command in a terminal session: $ sh springsource-tool-suite-2.9.0.RELEASE-e3.7.2-linux-gtk-installer.sh Follow the on-screen instructions to finish the installation. See “Running the STS Installer”.

How to find MYSQl Port No and Version ?

mysql> show variables like 'port'; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | port | 3306 | +---------------+-------+ 1 row in set (0.02 sec) mysql> show variables like 'version'; +---------------+-------------------+ | Variable_name | Value | +---------------+-------------------+ | version | 5.0.45-community-nt | +---------------+-------------------+ 1 row in set (0.00 sec)

Java JVM Shutdown Hook - tutorial

JVM shutdown hooks provide a clean and simple mechanism for registering application-specific behavior that performs the required cleanup work when a JVM terminates. It is a Java feature that let you have a piece of Java code run whenever the JVM terminates under one of the following conditions:   - The program exits normally, such as when the last non-daemon thread exits or when the                         Runtime.exit() method is invoked.   -  The virtual machine is terminated in response to a user interrupt, such as typing CTRL-C, or a                      system-wide event, such as user logoff or system shutdown (for example, the JVM receives               one of  the interrupt signals SIGHUP (Unix Only), SIGINT, or SIGTERM). A shutdow...

Java HashMap Example

The HashMap class uses a hash table to implement the Map interface. This allows the execution time of basic operations, such as get() and put() , to remain constant even for large sets. The following constructors are defined:   HashMap( ) HashMap(Map m ) HashMap(int capacity ) HashMap(int capacity , float fillRatio )   Hash map does not guarantee the order of its elements. Therefore, the order in which elements are added to a hash map is not necessarily the order in which they are read. Here is the code:   import java.util.HashMap; import java.util.Map; /**  *  * This Java HashMap example describes the basic operations performed on the HashMap  * @author abdul  *  */ public class HashMapExample {     public static void main(String args[]){                 // constructs a new empty HashMap with default initial capacity   ...

How to get free disk space of a drive in java ?

JDK 1.6 provides few new methods  getTotalSpace() , getFreeSpace() , bundled with java.io.File. These methods provides essential information regarding disk space. getFreeSpace() method -   Returns the number of unallocated bytes in the partition named by this abstract path name. getTotalSpace() method - Returns the size of the partition named by this abstract pathname. Here is the code:  import java.io.File; /**  * Program that returns the number of unallocated bytes , total space in the partition.  *  * @author abdul  *  */ public class DiskDetail {     public static void main(String[] args) {         File file = new File("C:");         long totalSpace = file.getTotalSpace(); // total disk space in bytes.         long freeSpace = file.getFreeSpace(); // unallocated / free disk space   ...

JAXB - II (jaxb.index file and ObjectFactory)

I was getting a Exception like, javax.xml.bind.JAXBException: "doesnt contain ObjectFactory.class or jaxb.index" while trying to create a JAXBContext using JAXBContext.newInstance(String contextPath). It took me a while to figure out what went wrong. So now that I've got things working correctly, I thought I'd post this example and solution to hopefully save you some time. When we create a marshaller, we first need to create a JAXBContext via its newInstance() factory method. You can create a context for a specific JAXB class  or you can create a context for a list of packages. There are two ways to resolve this issue :    - By creating ObjectFactory   - By adding jaxb.index file jaxb.index : The jaxb.index file is a text file contains a listing of the classes on the containing package that have JAXB annotations. Note : The name of the clases is their simple name not their classified name.   Rather than creating a ObjectFactory, I guess adding ...

Java Architecture for XML Binding (JAXB)

Overview:  - Java Architecture for XML Binding (JAXB) is a Java standard that defines how Java objects are converted to/from XML (specified using a standard set of mappings).  - It defines a programmer API for reading and writing Java objects to / from XML documents and a service provider which / from from XML documents allows the selection of the JAXB implementation  - It makes reading  and writing of XML via Java very easy.  - It allows Java developers to access and process XML data without having to know XML or XML processing  - It is used heavily by JAX-WS    - It provides ways to generate XML content from a Java representation , to generate a Java representation from XML file , to generate XML schema from Java Objects  - The JAXBContext class provides the client's entry point to the JAXB API. It provides an abstraction for managing the XML/Java binding information necessary to implement the JAXB binding framework operati...