FileSystem.java

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.RandomAccessFile;
import java.util.Date;
import java.util.LinkedList;
import java.util.Queue;
import java.util.TreeMap;
 

class FileSystem
{
	static int totalFileEntry=13250,clustersize=128,totalfat=163840;
	static RandomAccessFile file;
	static int sizeOfFileEntry,offFAT,sizeOfFATentry=3;
    static int offcreated=10,offmod=22,offsize=34,offpermi=37,offfirstcluster=38,offEnd=41,diskDataStartingPoint=1048020;
	static TreeMap<String, Integer> index = new TreeMap();
    static Queue<Integer> pqfE = new LinkedList();
    static Queue<Integer> pqfat = new LinkedList();
    static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    static String getName( int in ) throws Exception
    {
    	int address = getAddressFromFileEntry(in);
    	byte[] b = new byte[10];
    	file.seek(address);
    	file.read(b);
    	String a = byteToString(b);
    	StringBuilder name=new StringBuilder();
    	for( int i=0 ; i<10 ; i++ ) 
    	{
    		if( a.charAt(i)==(char)0 ) break;
    		name.append(a.charAt(i));
    	}
    	return name.toString();
    }
    
    static int getFirstCluster( int in ) throws Exception
    {
    	int address = getAddressFromFileEntry(in);
    	byte[] b = new byte[3];
    	file.seek(address+offfirstcluster);
    	file.read(b);
    	String a = byteToString(b);
    	return basetodec(a);
    }
    
    static String getDataFromFileEntry( int in, int offset, int len ) throws Exception
    {
    	int address = getAddressFromFileEntry(in);
    	byte[] b = new byte[len];
    	file.seek(address+offset);
    	file.read(b);
    	String a = byteToString(b);
    	return a;
    }
    
	public static void main(String[] args) throws Exception
    {
		sizeOfFileEntry=42;
		//totalFileEntry = (1024000-480000)/sizeOfFileEntry;
		offFAT = sizeOfFileEntry*totalFileEntry;
    	file = new RandomAccessFile("disk.txt","rw");
    	for( int i=0 ; i<totalFileEntry ; i++ )
    	{
    		file.seek(getAddressFromFileEntry(i+1));
    		byte[] b = new byte[1];
    		file.read(b);
    		if( (char)(b[0])==(char)0 )
    			pqfE.add(i+1);
    		else
    		{
    			String name = getName(i+1);
    			index.put(name, i+1);
    		}
    	}
    	
    	for( int i=0 ; i<totalfat ; i++ )
    	{
    		file.seek(getAddressFromfat(i+1));
    		byte[] b = new byte[3];
    		file.read(b);
    		String s = ""+(char)b[0]+(char)b[1]+(char)b[2];
    		if( basetodec(s)==0 )
    			pqfat.add(i+1);
    	}
    	
    	String instructions = 
    			"Enter\n"
			+"~ createf <filename>                  :  to create new file\n"
    			+"~ delf <filename>                     :  to delete this file\n"
    			+"~ readf <filename>                    :  to read the whole file\n"
    			+"~ writef append <filename>            :  to append into the existing file\n"
    			+"~ writef overwrite <filename>         :  to overwrite the existing file\n"
    			+"~ list                                :  to display the list the names of all files in system\n"
    			+"~ list -l                             :  to display the detailed list of all files in system\n"
    			+"~ list <filename>                     :  to display the detailed list of this file\n"
    			+"~ chmod <filename>                    :  to change the permissions of file\n"
    			+"~ renamef <oldFileName> <newFileName> :  to rename the file\n"
    			+"~ exit                                :  to exit the system\n"
    			;
    	System.out.println(instructions);
    	while( true )
    	{
    		System.out.print("\n>>>   ");
    		String[] s = br.readLine().split(" "); 
    		if( s[0].equals("createf") )
    		{
			if( s.length < 2 )
    			{
    				System.out.println("Not enough argument. Try again ...");
    	    			continue;
    			}    			
			else if( index.containsKey(s[1]) )
    			{
    				System.out.println("File with name \""+s[1]+"\" already exists. Try again with different name...");
    	    		continue;
    			}
    			char p=permi();
    			int is = createFile(s[1], p);
    			if( is==1 )
    				System.out.println("New File created successfully...");
    			else if( is==-1 )
    				System.out.println("Error...Sytem was unable to create new File. Try Again...  ");
    		}
    		else if( s[0].equals("delf") )
    		{
    			if( s.length < 2 )
    			{
    				System.out.println("Not enough argument. Try again ...");
    	    			continue;
    			}    			
			else if( index.containsKey(s[1]) )
    			{
    				delete(s[1]);
    				System.out.println("File with name \""+s[1]+"\" deleted successfully!");
    			}
    			else
    			{
    				System.out.println("Sorry! File with this name doesn't exist! Try Again . . .");
    			}
    		}
    		else if( s[0].equals("readf") )
    		{
    			if( s.length < 2 )
    			{
    				System.out.println("Not enough argument. Try again ...");
    	    			continue;
    			}    			
			else if( index.containsKey(s[1]) )
    			{
    				char pp = getDataFromFileEntry(index.get(s[1]), offpermi, 1).charAt(0);
					int[] per = getPer(pp);
					if( per[0]==1 || per[1]==1 )
					{
						int in = index.get(s[1]);
	    				int permi = basetodec(getDataFromFileEntry(in, offpermi, 1));
	    				StringBuilder con = new StringBuilder();
	    				readFile(s[1],con);
	    				System.out.println(con);
					}
					else
					{
						System.out.println("Sorry! This file has no read permissions.");
					}
    			}
    			else
    			{
    				System.out.println("Sorry! File with this name doesn't exist! Try Again . . .");
    			}
    		}
    		else if( s[0].equals("writef") )
    		{
    			if( s.length < 2 )
    			{
    				System.out.println("Sorry! File with this name doesn't exist! Try Again . . .");
    	    			continue;
    			}    			
			else if( s[1].equals("append") )
    			{
    				if( s.length < 3 )
	    			{
	    				System.out.println("Not enough argument. Try again ...");
	    	    			continue;
	    			}    			
				else if( index.containsKey(s[2]) )
	    			{
    					char pp = getDataFromFileEntry(index.get(s[2]), offpermi, 1).charAt(0);
    					int[] per = getPer(pp);
    					if( per[1]==1 )
    					{
    						int address = getAddressFromFileEntry(index.get(s[2]));
    						file.seek(address+offmod);
    				    	file.write(getCurrDateAndTime().getBytes());
    						
    						System.out.println("\nTo end writing in this file, please enter \"**exit**\" in new line\n");
                			StringBuilder sb = new StringBuilder();
                			String tem = br.readLine();
                			while( !tem.equals("**exit**") )
                			{
                				sb.append(tem+"\n");
                				tem = br.readLine();
                			}
                			if( sb.toString().length()==0 ) continue;
                			String sbb = sb.toString().substring(0, sb.length()-1);
                			int totalFreeBytes = clustersize*pqfat.size() + clustersize-basetodec(getDataFromFileEntry(index.get(s[2]),offEnd,3));// Check whether file exists?
                			if( totalFreeBytes>=sb.toString().length() )
                			{
                				appendFile(s[2],sbb.getBytes());
//                				System.out.println();
                			}
                			else
                				System.out.println("Error! Not Enough free space left in the disk! Delete some data and try again . . .");
    					}
    					else
    					{
    						System.out.println("Sorry! This file has no write permissions.");
    					}
    				}
    				else
    				{
    					System.out.println("Sorry! File with this name doesn't exist! Try Again . . .");
    				}
    			}
    			else if( s[1].equals("overwrite") )
    			{
    				if( s.length < 3 )
	    			{
	    				System.out.println("Not enough argument. Try again ...");
	    	    			continue;
	    			}    			
				else if( index.containsKey(s[2]) )
    				{
    					char pp = getDataFromFileEntry(index.get(s[2]), offpermi, 1).charAt(0);
    					int[] per = getPer(pp);
    					if( per[1]==1 )
    					{
    						System.out.println("\nTo end writing in this file, please enter \"**exit**\" in new line\n");
                			StringBuilder sb = new StringBuilder();
                			String tem = br.readLine();
                			while( !tem.equals("**exit**") )
                			{
                				sb.append(tem+"\n");
                				tem = br.readLine();
                			}
                			if( sb.toString().length()==0 ) continue;
                			String sbb = sb.toString().substring(0, sb.length()-1);
                			int totalFreeBytes = clustersize*(pqfat.size()+basetodec(getDataFromFileEntry(index.get(s[2]), offsize, 3)));
                			if( totalFreeBytes>=sbb.length() )
                			{
                				char permissions = getDataFromFileEntry(index.get(s[2]),offpermi,1).charAt(0);
                				String created="";
                				created = getDataFromFileEntry(index.get(s[2]),offcreated,12);
                				
                				delete(s[2]);
                				createFile(s[2], permissions);
                				int address = index.get(s[2]);
                				file.seek(address+offcreated);
                				file.write(created.getBytes());
                				appendFile(s[2],sbb.getBytes());
//                				System.out.println();
                			}
                			else
                				System.out.println("Error! Not Enough free space left in the disk! Delete some data and try again . . .");
    					}
    					else
    					{
    						System.out.println("Sorry! This file has no write permissions.");
    					}
    				}
    				else
    				{
    					System.out.println("Sorry! File with this name doesn't exist! Try Again . . .");
    				}
    			}
    			else
    			{
    				System.out.println("write append or overwrite in argument and try Again . . .");
    			}
    		}
    		else if( s[0].equals("cpf") )
    		{
    			if( s.length < 2 )
    			{
    				System.out.println("Not enough argument. Try again ...");
    	    			continue;
    			}    			
			else if( index.containsKey(s[1]) )
    			{
    				changePermissions(s[1]);
    			}
    			else
    			{
    				System.out.println("Sorry! File with this name doesn't exist! Try Again . . .");
    			}
    		}
    		else if( s[0].equals("renamef") )
    		{
    			if( s.length < 2 )
    			{
    				System.out.println("Not enough argument. Try again ...");
    	    			continue;
    			}    			
			else if( s[1].length()<=10 )
    			{
    				if( index.containsKey(s[1]) )
        			{
        				rename(s[1],s[2]);
        			}
        			else
        			{
        				System.out.println("Sorry! File with this name doesn't exist! Try Again . . .");
        			}
    			}
    			else
    			{
    				System.out.println("Name of file should be less than or equal to 10 characters");
    			}
    		}
    		else if( s[0].equals("list") )
    		{
    			if( s.length>1 )
    			{
    				String header="Name Of File        File created Date/Time        Last Modified Date/Time        Size        Permissions";
        			System.out.println(header);
        			System.out.println();
    				if( s[1].equals("-l") )
    				{
    					displayfileList(0,null);
    				}
    				else
    				{
    					if( index.containsKey(s[1]) )
    						displayfileList(2,s[1]);
    					else
    						System.out.println("Sorry! File with this name doesn't exist! Try Again . . .");
    				}
    			}
    			else
    			{
    				displayfileList(1,null);
    			}
    		}
		else if( s[0].equals("exit") )
    		{
			System.exit(0);
    		}
    		else
    		{
    			System.out.println("Invalid command");
    		}
    	}
    }
	
	static int[] getPer( char c )
	{
		int p = (int)c-'0';
		String permissions = new String(); 
    	while( p!=0 )
    	{
    		permissions+=(p%2);
    		p/=2;
    	}
    	for( int i=0 ; permissions.length()<3 ; i++ ) permissions+=0;
    	return new int[]{(int)permissions.charAt(2)-'0',(int)permissions.charAt(1)-'0',(int)permissions.charAt(0)-'0'};
	}
	
	static void displayfileList(int flag, String name ) throws Exception
	{
		StringBuilder sb = new StringBuilder();
		for( int i=1 ; i<=totalFileEntry ; i++ )
    	{
			int address=getAddressFromFileEntry(i);
    		file.seek(address);
    		byte[] b = new byte[1];
    		file.read(b);
    		if( (char)(b[0])!=(char)0 )
    		{
    			String interpretation = interprete(address,i);
    			if( flag==0 )
    			{
    				sb.append(interpretation+"\n");
    			}
    			else if( flag==1 )
    			{
    				String[] sp = interpretation.split("        ");
    				sb.append(sp[0]+"\n");
    			}
    			else
    			{
    				String[] sp = interpretation.split("        ");
    				if( sp[0].equals(name) )
    				{
    					sb.append(interpretation+"\n"); break;
    				}
    			}
    		}
    	}
		System.out.println(sb);
	}
	
	static String interprete( int address, int ind ) throws Exception
	{
		byte[] b = new byte[sizeOfFileEntry];
		file.seek(address);
		file.read(b);
		String a = byteToString(b);
		StringBuilder name=new StringBuilder();
    	for( int i=0 ; i<10 ; i++ ) 
    	{
    		if( a.charAt(i)==(char)0 ) break;
    		name.append(a.charAt(i));
    	}
    	String Name = name.toString(); 
    	while( Name.length()<20 ) Name+=" ";
    	String created = getFormatted(a.substring(10,22));
    	while( created.length()<30 ) created+=" ";
    	String modified = getFormatted(a.substring(22,34));
    	while( modified.length()<31 ) modified+=" ";
    	String size = String.valueOf(128*basetodec(getDataFromFileEntry(ind, offsize, 3)));
    	while( size.length()<12 ) size+=" ";
    	int p = (int)getDataFromFileEntry(ind, offpermi, 1).charAt(0)-'0';
    	StringBuilder permissions = new StringBuilder(); 
    	while( p!=0 )
    	{
    		permissions.append(p%2);
    		p/=2;
    	}
    	for( int i=0 ; permissions.length()<3 ; i++ ) permissions.append('0');
    	return Name+created+modified+size+permissions.reverse();
	}
	
	static String getFormatted( String date1 )
	{
    	String res="";
    	String[] month={"Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"};
    	String mon = month[Integer.parseInt(date1.substring(2, 4))];
    	res+=mon+" ";
    	res+=date1.substring(0,2)+" "+date1.substring(4,8)+" ";
    	res+=date1.substring(8,10)+":"+date1.substring(10,12);
    	return res;
	}
	
	static void rename( String oldName, String newName ) throws IOException
	{
		int ind = index.get(oldName);
		index.remove(oldName);
		index.put(newName, ind);
		StringBuilder sb = new StringBuilder();
		for( int i=0 ; i<offcreated ; i++ )
			sb.append((char)0);
		int address = getAddressFromFileEntry(index.get(newName));
		file.seek(address);
		file.write(sb.toString().getBytes());
		file.seek(address);
		file.write(newName.getBytes());
	}
	
	static char permi() throws IOException
	{
		char temp;
		String p="";
		System.out.println("Read Only Permissions? y/n \t");
		temp=br.readLine().charAt(0);
		while( temp!='y' && temp!='n' )
		{
			System.out.println("Try Again...");
			System.out.println("Read Permissions? y/n \t");
			temp=br.readLine().charAt(0);
		}
		if( temp=='y' ) p+='1';
		else p+='0';
			
		System.out.println("Read/Write Permissions? y/n \t");
		temp=br.readLine().charAt(0);
		while( temp!='y' && temp!='n' )
		{
			System.out.println("Try Again...");
			System.out.println("Read/Write Permissions? y/n \t");
			temp=br.readLine().charAt(0);
		}
		if( temp=='y' ) p+='1';
		else p+='0';
		
		System.out.println("Execute Permissions? y/n\t");
		temp=br.readLine().charAt(0);
		while( temp!='y' && temp!='n' )
		{
			System.out.println("Try Again...");
			System.out.println("Execute Permissions? y/n\t");
			temp=br.readLine().charAt(0);
		}
		if( temp=='y' ) p+='1';
		else p+='0';
		
		int p1 = 4*(p.charAt(0)-'0')+2*(p.charAt(1)-'0')+(p.charAt(2)-'0');
		return (char)(p1+'0');
	}
	
	static void changePermissions( String name ) throws IOException
	{
		int ind = index.get(name);
		char p = permi();
		int address = getAddressFromFileEntry(ind);
		file.seek(address+offpermi);
		file.write((p+"").getBytes());
	}
	
	static void delete( String name ) throws Exception
	{
		int ind=index.get(name);
		index.remove(name);
		pqfE.add(ind);
		int address=getAddressFromFileEntry(ind);
		byte[] b = new byte[3];
		file.seek(address+offfirstcluster);
		file.read(b, 0, 3);
		String a = byteToString(b);
		int curr=basetodec(a);
		
		int next = getNextCluster(curr);
		file.seek(getAddressFromfat(curr));
		file.write(((char)(0)+""+(char)(0)+""+(char)(0)).getBytes());
		pqfat.add(curr);
		while( next!=(totalfat+1) )
		{
			curr=next;
			next = getNextCluster(next);
			file.seek(getAddressFromfat(curr));
			file.write(((char)(0)+""+(char)(0)+""+(char)(0)).getBytes());
			pqfat.add(curr);
		}
		file.seek(address);
		StringBuilder sb=new StringBuilder();
		for( int i=0 ; i<sizeOfFileEntry ; i++ )
			sb.append((char)0);
		file.write(sb.toString().getBytes());
	}
	
	static void appendFile(  String name, byte[] toBeAppended ) throws Exception
	{
		int ind = index.get(name);
		int firstCluster = basetodec(getDataFromFileEntry(ind, offfirstcluster, 3));
		int next = getNextCluster(firstCluster);
		int endOfFile = basetodec(getDataFromFileEntry(ind, offEnd, 1));
		if( next==(totalfat+1) )
		{
			int addressData = getDataAddress(firstCluster);
			file.seek(addressData+endOfFile);
			int noOfBytesToBeWritten = Math.min(clustersize-endOfFile, toBeAppended.length);
			file.write(toBeAppended, 0, noOfBytesToBeWritten);
			
			if( noOfBytesToBeWritten==toBeAppended.length )
			{
				setEndOfFile(ind, endOfFile+noOfBytesToBeWritten);
			}
			else
			{
				next = pqfat.poll();
				
				setSizeOfFile(ind,1,"add");
				
				setFATEntry(firstCluster, next);
				
				setFATEntry(next, totalfat+1);
				
				append( next, toBeAppended, noOfBytesToBeWritten, -1, ind );
			}
		}
		else
		{
			append( next, toBeAppended, 0, endOfFile, ind );
		}
	}
	
	static void append( int curr, byte[] toBeAppended, int offsetOfString, int endOfFile, int ind ) throws Exception
	{
		if( endOfFile<0 )
		{
			int addressData = getDataAddress(curr);
			int noOfBytesToBeWritten = Math.min(clustersize, toBeAppended.length-offsetOfString);
			file.seek(addressData);
			file.write(toBeAppended, offsetOfString, noOfBytesToBeWritten);
			offsetOfString+=noOfBytesToBeWritten;
			if( offsetOfString==toBeAppended.length )
			{
				setEndOfFile( ind, noOfBytesToBeWritten );
			}
			else
			{
				int next = pqfat.poll();
				setSizeOfFile(ind,1,"add");
				setFATEntry(curr,next);
				setFATEntry(next,totalfat+1);
				append( next, toBeAppended, offsetOfString, endOfFile, ind );
			}
		}
		else
		{
			int next = getNextCluster(curr);
			if( next==(totalfat+1) )
			{
				int addressData = getDataAddress(curr);
				file.seek(addressData+endOfFile);
				int noOfBytesToBeWritten = Math.min(clustersize-endOfFile, toBeAppended.length);
				file.write(toBeAppended, 0, noOfBytesToBeWritten);
				offsetOfString+=noOfBytesToBeWritten;
				if( offsetOfString==toBeAppended.length )
				{
					setEndOfFile(ind, noOfBytesToBeWritten+endOfFile);
				}
				else
				{
					next = pqfat.poll();
					setSizeOfFile(ind,1,"add");
					setFATEntry(curr, next);
					setFATEntry(next, totalfat+1); 
					append(next,toBeAppended,noOfBytesToBeWritten,-1,ind);
				}
			}
			else
			{
				append(next,toBeAppended,offsetOfString,endOfFile,ind);
			}
		}
	}
	
	static void setSizeOfFile( int ind, int size, String op ) throws Exception
	{
		int address = getAddressFromFileEntry(ind);
		if( op.equals("add") )
		{
			int oldsize = basetodec(getDataFromFileEntry(ind, offsize, 3));
			file.seek(address+offsize);
			file.write(regulate(decTo128(oldsize+size), 3).getBytes());
		}
		else
		{
			file.write(regulate(decTo128(size), 3).getBytes());
		}
	}
	
	static void setFATEntry( int curr, int next ) throws Exception
	{
		int addressFAT = getAddressFromfat(curr);
		file.seek(addressFAT);
		file.write(regulate(decTo128(next),3).getBytes());
		return;
	}
	
	static void setEndOfFile( int ind, int endOfFile ) throws Exception
	{
		int address = getAddressFromFileEntry(ind);
		file.seek(address+offEnd);
		file.write(regulate(decTo128(endOfFile), 1).getBytes());
		return;
	}
	
	static void readFile( String name, StringBuilder con ) throws Exception
	{
		int ind = index.get(name);
		int firstCluster = basetodec(getDataFromFileEntry(ind,offfirstcluster,3));
		int endOfFile = basetodec(getDataFromFileEntry(ind, offEnd, 1));
		read( firstCluster, con, endOfFile );
	}
	
	static void read( int in, StringBuilder con, int endOfFile ) throws Exception
	{
		int next = getNextCluster(in);
		if( next!=(totalfat+1) )
		{
			byte[] b = new byte[clustersize];
			file.seek(getDataAddress(in));
			file.read(b);
			String a = byteToString(b);
			con.append(a);
			read( next, con, endOfFile );
		}
		else
		{
			if( endOfFile==0 ) return;
			byte[] b = new byte[endOfFile];
			file.seek(getDataAddress(in));
			file.read(b);
			String a = byteToString(b);
			con.append(a);
		}
	}
	
	static int getDataAddress( int clusterNo )
	{
		return diskDataStartingPoint+(clusterNo-1)*clustersize;
	}
	
	
	
	static int getNextCluster( int n ) throws Exception
	{
		int address1 = getAddressFromfat(n);
		byte[] b = new byte[3];
		file.seek(address1);
		file.read(b);
		String a = byteToString(b);
		return basetodec(a);
	}
	
    static int createFile( String name, char permissions ) throws Exception
    {
    	
    	if( name.length()>10 || (int)permissions>55 || pqfE.size()==0 || pqfat.size()==0 ) return -1;
    	
    	int first = pqfE.poll();
    	index.put(name, first);
    	int firstfat=pqfat.poll();
    	int address=getAddressFromFileEntry(first);
    	
    	file.seek(address);
    	file.write(name.getBytes());
    	
    	file.seek(address+offcreated);
    	file.write(getCurrDateAndTime().getBytes());
    	
    	file.seek(address+offmod);
    	file.write(getCurrDateAndTime().getBytes());
    	
    	file.seek(address+offsize);
    	file.write(regulate(decTo128(1),3).getBytes());
    	
    	file.seek(address+offpermi);
    	file.write((permissions+"").getBytes());
    	
    	file.seek(address+offfirstcluster);
    	file.write(regulate(decTo128(firstfat),3).getBytes());
    	
    	setFATEntry(firstfat, totalfat+1);
    	
    	file.seek(address+offEnd);
    	file.write(decTo128(0).getBytes());
    	return 1;
    }
    
    static String byteToString( byte[] b )
	{
		String s="";
		for( int i=0 ; i<b.length ; i++ )
			s+=(char)b[i];
		return s;
	}
    
    static int getAddressFromFileEntry( int i )
    {
    	return sizeOfFileEntry*(i-1);
    }
    
    static int getAddressFromfat( int i )
    {
    	return offFAT+sizeOfFATentry*(i-1);
    }
    
    static String decTo128( int n )
    {
    	StringBuilder sb = new StringBuilder();
    	while( n>0 )
    	{
    		int rem = n%128;
    		sb.append((char)rem);
    		n/=128;
    	}
    	return sb.reverse().toString();
    }
    
    static int basetodec( String s128 )
    {
    	int p=1;int res=0;
    	for( int i=s128.length()-1 ; i>=0 ; i-- )
    	{
    		res += p*(int)(s128.charAt(i));
    		p*=128;
    	}
    	return res;
    }
    
    static String regulate( String s, int n )
    {
    	String res="";
    	for( int i=0 ; i+s.length()<n ; i++ )
    		res+=(char)0;
    	res+=s;
    	return res;
    }
    
    static String getCurrDateAndTime()
    {
    	Date d = new Date();
    	String[] dt = d.toString().split(" ");
    	String res = "";
    	TreeMap<String,String> tm = new TreeMap();
    	tm.put("Jan", "01");    	tm.put("Feb", "02");    	tm.put("Mar", "03");    	tm.put("Apr", "04");
    	tm.put("May", "05");    	tm.put("Jun", "06");    	tm.put("Jul", "07");    	tm.put("Aug", "08");
    	tm.put("Sep", "09");    	tm.put("Oct", "10");    	tm.put("Nov", "11");    	tm.put("Dec", "12");
    	res=dt[2]+tm.get(dt[1])+dt[5]+dt[3].charAt(0)+dt[3].charAt(1)+dt[3].charAt(3)+dt[3].charAt(4);
    	return res;
    }
    
}