import java.util.Scanner;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

public class Test {
	public static void main(String[] args) {
		String urlPattern = "^http(s{0,1})://[a-zA-Z0-9_/\\-\\.]+\\.([A-Za-z/]{2,5})[a-zA-Z0-9_/\\&\\?\\=\\-\\.\\~\\%]*";
		Scanner scanner = new Scanner(System.in);

		System.out.println("Enter URL to check ");

		String url = scanner.nextLine();
		Pattern patt = Pattern.compile(urlPattern);
		Matcher matcher = patt.matcher(url);

		System.out.println(matcher.matches());
	}

}

	

Here you will find the code base to search for the list of columns in a table in Oracle DB.
Note* : You need to provide the oracle DB related details in code(e.g. userId & password etc)

/*
 * Here we will learn to access columns in tables using DB Metadata
 */
package jbt;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class AccessTableCoulmn {

	public static void main(String[] args) throws SQLException,
			ClassNotFoundException {

		Class.forName("oracle.jdbc.OracleDriver");
		String serverName = "172.20.6.34";
		String portNumber = "1541";
		String sid = "NCSS10DV";
		String url = "jdbc:oracle:thin:@" + serverName + ":" + portNumber + ":"
				+ sid;
		String username = "ncsdba";
		String password = "mig123";
		Connection conn = DriverManager.getConnection(url, username, password);

		Statement stmt = conn.createStatement();
		ResultSet rs = stmt
				.executeQuery("SELECT column_name, data_type, data_length"
						+ " FROM user_tab_columns"
						+ " WHERE table_name = 'JBT_TABLE'");

		while (rs.next()) {
			System.out.print(rs.getString(1));
			System.out.print(" ");
			System.out.print(rs.getString(2));
			System.out.print(" ");
			System.out.println(rs.getString(3));
		}

	}
}

/*
 * Here we will learn to connect to DB
 */

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Scanner;

public class CreateConnectionToDB {

	public static void main(String[] args) throws SQLException,
			ClassNotFoundException {

		Scanner scanner = new Scanner(System.in);
		System.out.println("Enter DB host address");
		String serverName = scanner.next();

		System.out.println("Enter DB port");
		String portNumber = scanner.next();

		System.out.println("Enter DB userId");
		String username = scanner.next();

		System.out.println("Enter DB Password");
		String password = scanner.next();

		System.out.println("Enter DB SID or Service name");
		String sid = scanner.next();

		Class.forName("oracle.jdbc.OracleDriver");
		System.out.println("Oracle driver loaded Successfully.");

		String url = "jdbc:oracle:thin:@" + serverName + ":" + portNumber + ":"
				+ sid;
		Connection conn = DriverManager.getConnection(url, username, password);

		System.out.println("Connection to DB is successful");

	}
}

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

public class CreateTableInDB {

	public static void main(String[] args) throws SQLException,
			ClassNotFoundException {

		Class.forName("oracle.jdbc.OracleDriver");

		String serverName = "";
		String portNumber = "1541";
		String sid = "";
		String url = "jdbc:oracle:thin:@" + serverName + ":" + portNumber + ":"
				+ sid;
		String username = "";
		String password = "";
		Connection conn = DriverManager.getConnection(url, username, password);

		Statement stmt = conn.createStatement();
		stmt.executeUpdate("create table jbt_table(name varchar2(12))");
		System.out.println("Table Creation Successful");
	}

}

To check the default date format of Oracle Db find below the code base. You need to provide Oracle related details in programme.

package com.db;

/*
 * Here we will learn to get default Date format of Oracle DB.
 */

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DefaultDateFormat {

	public static void main(String[] args) throws SQLException,
			ClassNotFoundException {

		Class.forName("oracle.jdbc.OracleDriver");

		String serverName = "";
		String portNumber = "1541";
		String sid = "";
		String url = "jdbc:oracle:thin:@" + serverName + ":" + portNumber + ":"
				+ sid;
		String username = "";
		String password = "";
		Connection conn = DriverManager.getConnection(url, username, password);

		Statement stmt = conn.createStatement();
		ResultSet rs = stmt
				.executeQuery("SELECT VALUE  FROM v$parameter WHERE UPPER (NAME) = 'NLS_DATE_FORMAT'");

		while (rs.next()) {
			System.out.print(rs.getString(1));
		}
	}
}

import java.io.File;
import java.util.Scanner;

/*
 * Here we will learn to check if file is read only or not?
 */
public class IsFileReadOnly {

	public static void main(String[] args) {

		Scanner scanner = new Scanner(System.in);
		System.out.println("Enter the path of File");
		String filePath = scanner.nextLine();
		File file = new File(filePath);

		if (file.isDirectory()) {
			System.err.println("Given path is of Directory and not of File.");
			System.exit(0);
		} else {
			if (file.canWrite()) {
				System.out.println("File is writtable.");
			} else
				System.err
						.println("File is not Read Only.");
		}

	}
}

import java.io.File;
import java.util.Scanner;

/*
 * Here we will learn to check if given directory is hidden or not.
 */
public class IsDirHidden {

	public static void main(String[] args) {

		Scanner scanner = new Scanner(System.in);
		System.out.println("Enter the path of Directory to check.");
		String dirPath = scanner.nextLine();

		File file = new File(dirPath);
		if (file.isDirectory()) {
			if (file.isHidden())
				System.out.println("Directory is Hidden");
			else
				System.out.println("Directory is not Hidden");
		} else
			System.err.println("This is not a directory");
	}
}

This example will show you the way to rename any folder in Java.

import java.io.File;
import java.util.Scanner;

/*
 * Here we will learn to rename a Directory.
 */
public class RenameDir {
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		System.out.println("Enter the path of directory to rename.");
		String dirPath = scanner.nextLine();
		File dir = new File(dirPath);
		if (!dir.isDirectory()) {
			System.err.println("There is no directory @ given path");
			System.exit(0);
		}

		System.out
				.println("Enter new name of directory(Only Name and Not Path).");
		String newDirName = scanner.nextLine();

		File newDir = new File(dir.getParent() + "\" + newDirName);
		dir.renameTo(newDir);

		System.out.println("Done");
	}
}

Here we are discussing about reading the file using Scanner.

To learn to read File using BufferedInputStream  Click Here.

To learn to read File using BufferedReader  Click Here.

package JavaIOExample;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

/*
 * Here we will learn to read the file using Scanner.
 */
public class ReadTheFileUsingScanner {

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		System.out.println("Enter the File path");
		String filePath = scanner.next();

		/*
		 * Creates a new File instance by converting the given pathname string
		 * into an abstract pathname.
		 */
		File file = new File(filePath);

		Scanner scannerFile = null;

		try {
			/*
			 * Constructs a new Scanner that produces values scanned from the
			 * specified file. Bytes from the file are converted into characters
			 * using the underlying platform's default charset.
			 */
			scannerFile = new Scanner(file);

			/*
			 * Returns true if this scanner has another token in its input.
			 */
			while (scannerFile.hasNext())
				/*
				 * Finds and returns the next complete token from this scanner.
				 * A complete token is preceded and followed by input that
				 * matches the delimiter pattern.
				 */
				System.out.println(scannerFile.next());

		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} finally {
			scanner.close();
		}
	}

}

Here we are discussing about reading the file using BufferedInputStream.

To learn to read File using BufferedReader  Click Here.

To learn to read File using Scanner  Click Here.

package JavaIOExample;

import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Scanner;

/*
 * Here we will learn to read the file using BufferedInputStream. 
 */
public class ReadTheFileUsingBufferedInputStream {
	@SuppressWarnings("deprecation")
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		System.out.println("Enter the File path");
		String filePath = scanner.next();

		BufferedInputStream bis = null;
		DataInputStream dis = null;
		FileInputStream fis = null;

		/*
		 * Creates a new File instance by converting the given pathname string
		 * into an abstract pathname. 
		 */
		File file = new File(filePath);

		try {
			fis = new FileInputStream(file);

			bis = new BufferedInputStream(fis);
			dis = new DataInputStream(bis);

			while (dis.available() != 0) {
				/*
				 * Read the next line of text from this input stream.
				 * Deprecated
				 */
				System.out.println(dis.readLine());
			}

		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				fis.close();
				bis.close();
				dis.close();
			} catch (IOException e) {
				e.printStackTrace();
			}

		}
	}

}