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
Loading multiple instances by list of entity ids
From hibernate 5.1 we can load multiple instances of same class type in one shot by using the list of ids. The below code gives an example of this import java.util.List; import org.hibernate.MultiIdentifierLoadAccess; import org.hibernate.Session; import org.hibernate.SessionFactory; import model.Series; public class HibernateDemo { public static void main(String[] args) { SessionFactory sessionFactory = HibernateUtil.createSessionFactory(); Session session…… Continue reading Loading multiple instances by list of entity ids
Writing JSON Data in a streaming way
This post explains how to write json data to a file using JsonGenerator. The previous post explains the same using JsonWriter. The difference is that to use JsonWriter we need to build the entire object (which represents json data) in memory before writing to a file. Whereas with JsonGenerator we dont need to build the…… Continue reading Writing JSON Data in a streaming way
Updating a particular element in JAXB generated xml
Sometimes xml documents are very big and our requirement is to update a particular section of the document. JAXB binder comes to our help. Binder object maintains the mapping between the java object and xml infoset like DOM. Any modification to java object can be synchronized to xml held by binder object and vice versa.…… Continue reading Updating a particular element in JAXB generated xml
Code Recipes Blog 