Found 9326 Articles for Object Oriented Programming

What are file operations in Java?

Monica Mona
Updated on 25-Feb-2020 10:23:05

166 Views

File class provides various methods to perform respective file operations.canRead(): This method tests whether the application can read the file denoted by this abstract pathname. It returns true if and only if the file specified by this abstract pathname exists and can be read by the application; false otherwise.canWrite(): This method tests whether the application can modify the file denoted by this abstract pathname. It returns true if and only if the file system actually contains a file denoted by this abstract pathname and the application is allowed to write to the file; false otherwise.createNewFile(): This method atomically creates a ... Read More

How to perform sort using Java?

karthikeya Boyini
Updated on 20-Feb-2020 09:52:19

71 Views

You can sort an array using sort() method of the Arrays class.ExampleLive Demoimport java.util.Arrays; public class MainClass {    public static void main(String args[]) throws Exception {       int array[] = { 2, 5, -2, 6, -3, 8, 0, -7, -9, 4 };       Arrays.sort(array);       printArray("Sorted array", array);       int index = Arrays.binarySearch(array, 1);       System.out.println("Didn't find 1 @ " + index);       int newIndex = -index - 1;       array = insertElement(array, 1, newIndex);       printArray("With 1 added", array);    }   ... Read More

How to calculate the size of folder using Java?

Sharon Christine
Updated on 20-Feb-2020 09:51:17

1K+ Views

You can get the size of a directory with the help of FileUtils.sizeofDirectory(File Name) method of FileUtils class.Exampleimport java.io.File; import org.apache.commons.io.FileUtils; public class Main {    public static void main(String[] args) {       long size = FileUtils.sizeOfDirectory(new File("C:/Windows"));       System.out.println("Size: " + size + " bytes");    } }OutputSize: 2048 bytes

How to find the file using Java?

Swarali Sree
Updated on 30-Jul-2019 22:30:20

99 Views

Following example shows the way to look for a particular file in a directory by creating a File filter. Following example displays all the files having file names beginning with 'b'.ExampleLive Demoimport java.io.*; public class Main {    public static void main(String[] args) {       File dir = new File("C:");             FilenameFilter filter = new FilenameFilter() {          public boolean accept (File dir, String name) {             return name.startsWith("b");          }       };       String[] children = ... Read More

How to create a Directory recursively using Java?

Samual Sam
Updated on 20-Feb-2020 09:49:22

189 Views

The java.io.File.mkdirs() creates the directory named by this abstract pathname, together with necessary and non-existent parent directories.ExampleLive Demoimport java.io.File; public class Main {    public static void main(String[] args) {       String directories = "D:\a\b\c\d ";       File file = new File(directories);       boolean result = file.mkdirs();       System.out.println("Status = " + result);    } }OutputStatus = true

How to check the Existence of a File using Java?

Monica Mona
Updated on 20-Feb-2020 08:27:51

96 Views

The file class provides a method named exists() which returns true if the file specified in the current file object exists.ExampleLive Demoimport java.io.File; public class FileHandling {    public static void main(String args[]) {       File file = new File("samplefile");       if(file.exists()) {          System.out.println("Given file existed");       } else {          System.out.println("Given file does not existed");      }    } }OutputGiven file does not existed

How to list all files in a directory using Java?

karthikeya Boyini
Updated on 20-Feb-2020 08:21:45

758 Views

You can get the list of files in a directory −Create a directory object using the File class.Get the list of directories in it using the getName() method.Exampleimport java.io.File; public class FindingDirectories {    public static void main(String args[]) {       String dir ="C:/Users/Tutorialspoint/Desktop/movies";       File directory = new File(dir);       File[] fileList = directory.listFiles();       for(File file: fileList) {          System.out.println(file.getName());       }    } }OutputArundhati HD.mp4 Okka Ammai Tappa.mkv Padamati Sandhya Ragam.mp4

What is the difference between System.out.println() and System.out.print() in Java?

Sharon Christine
Updated on 20-Feb-2020 08:19:37

1K+ Views

The println() terminates the current line by writing the line separator string. The print() method just prints the given content.ExampleLive Demopublic class Sample {    public static void main(String args[]) {       System.out.println("Hello");       System.out.println("how are you");       System.out.print("Hello");       System.out.print("how are you");    } }OutputHello how are you Hellohow are you

What is the difference between System.out, System.in and System.err streams in Java?

Swarali Sree
Updated on 30-Jul-2019 22:30:20

951 Views

All the programming languages provide support for standard I/O where the user's program can take input from a keyboard and then produce an output on the computer screen. Similarly, Java provides the following three standard streams:Standard Input: This is used to feed the data to user's program and usually a keyboard is used as a standard input stream and represented as System.in.Standard Output: This is used to output the data produced by the user's program and usually a computer screen is used for standard output stream and represented as System.out.Standard Error: This is used to output the error data produced ... Read More

What is the difference between Serialization and Deserialization in Java?

Samual Sam
Updated on 25-Feb-2020 10:28:26

2K+ Views

Serialization Java provides a mechanism, called object serialization where an object can be represented as a sequence of bytes that includes the object's data as well as information about the object's type and the types of data stored in the object.Exampleimport java.io.*; public class SerializeDemo {    public static void main(String [] args) {       Employee e = new Employee();       e.name = "Reyan Ali";       e.address = "Phokka Kuan, Ambehta Peer";       e.SSN = 11122333;       e.number = 101;       try {         ... Read More

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