Getting mapped class meta data

This post explains how to get hibernate related meta data information of a mapped class. Class package model; public class Series { private Integer id; private String name; private String description; public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getName() { return name; } public…… Continue reading Getting mapped class meta data

Creating dynamic proxy objects

This post explains how to create proxy objects using Java Proxy api. We need the below items to create a proxy. 1) proxy interfaces (list of interfaces the dynamic proxy class will implement). 2) dynamic proxy class is proxy class generated at runtime and implements the proxy interfaces. 3) proxy instance is an instance of…… Continue reading Creating dynamic proxy objects

Listening to unmarshalling events

By subclassing Unmarshaller.Listener abstract class, we can create listener class which will listen to unmarshling events. We can add our code if we want to perform some actions before and after unmarshalling. The Unmarshaller.Listener class has two methods which can be overridden. By default the methods doesn’t perform any actions. 1) public void beforeUnmarshal(Object target,…… Continue reading Listening to unmarshalling events

Listening to marshaling events

By subclassing Marshaller.Listener abstract class, we can create listener class which will listen to marshling events. We can add our code if we want to perform some actions before and after marshalling. The Marshaller.Listener class has two methods which can be overridden. By default the methods doesn’t perform any actions. 1) public void beforeMarshal(Object source)…… Continue reading Listening to marshaling events

Unzipping a zip file and checking for data integrity

This post explains how to unzip a zip file and check whether data were correctly extracted. package ZipDemo; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.util.Enumeration; import java.util.zip.CRC32; import java.util.zip.CheckedInputStream; import java.util.zip.ZipEntry; import java.util.zip.ZipFile; public class ZipDemo6 { public static void main(String[] args) throws FileNotFoundException, IOException { String destination = “E:\\Projects\\JavaProjects\\JavaConcepts\\WorkFolder\\Folder1”;…… Continue reading Unzipping a zip file and checking for data integrity

Unzipping a zip file

This post explains how to unzip a zip file. package ZipDemo; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.util.Enumeration; import java.util.zip.ZipEntry; import java.util.zip.ZipFile; public class ZipDemo3 { public static void main(String[] args) throws FileNotFoundException, IOException { String destination = “E:\\Projects\\JavaProjects\\JavaConcepts\\WorkFolder\\Folder1”; try (ZipFile zipFile = new ZipFile(“E:\\Projects\\JavaProjects\\JavaConcepts\\WorkFolder\\Folder1.zip”)){ File folder = new File(destination);…… Continue reading Unzipping a zip file

Creating a zip file of a folder

This post explains how to create a zip file of a folder (also containing sub folders) The below image shows the hierarchy of the folder package ZipDemo; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.nio.file.Path; import java.nio.file.Paths; import java.util.zip.ZipEntry; import java.util.zip.ZipOutputStream; public class ZipDemo2 { private File startingFolder; public ZipDemo2(File startingFolder)…… Continue reading Creating a zip file of a folder

Exploring a zip file

This post explains how to explore a zip file. Main Code package ZipDemo; import java.io.IOException; import java.util.Enumeration; import java.util.zip.ZipEntry; import java.util.zip.ZipFile; public class ZipDemo1 { public static void main(String[] args) { try (ZipFile zipFile = new ZipFile(“E:\\Projects\\JavaProjects\\JavaConcepts\\WorkFolder\\Folder1.zip”)){ Enumeration entries = zipFile.entries(); for (Enumeration e = entries; e.hasMoreElements();) { ZipEntry entry = e.nextElement(); System.out.println(entry.getName()); } }…… Continue reading Exploring a zip file

Programmatically generating schema for java classes

This post will explain how to generate schema files for java classes programmatically. The schema is generated by an instance of JAXBContext. In addition to JAXBContext we also need SchemaOutputResolver for this purpose. The SchemaOutputResolver class is an abstract class so we need to create a new class extending SchemaOutputResolver as shown below. package JAXB;…… Continue reading Programmatically generating schema for java classes

Reading json data in streaming way

This post explains how to read json data as a stream. The previous post explains the same using JsonReader. The difference is that to use JsonReader we need to build the entire object (which represents json data) in memory. Whereas with JsonParser we dont need to build the entire object. The below code explains how…… Continue reading Reading json data in streaming way