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TOVAL comprises a set of java classes for common programming issues. It includes utils for arrays, lists, sets and collections for convenient handling and modification, but also support for mathematic definitions concerning logic (clauses + resolution) together with some algorithms for permutations, powersets and resolution. Additionally it contains a number of types for multisets, matrices with object keys and much more.

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package de.invation.code.toval.file;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.nio.charset.Charset;

public class FileReader {
	
	protected Charset charset = Charset.forName("UTF-8");
	protected BufferedReader input = null;
	protected File inputFile = null;
	protected String systemLineSeparatorBackup = null;
	
	//------- Constructors --------------------------------------------------------------------
	
	public FileReader(String fileName) throws IOException{
		initialize(fileName);
	}
	
	public FileReader(String fileName, Charset charset) throws IOException{
		setCharset(charset);
		initialize(fileName);
	}
	
	//------- Getters and Setters -------------------------------------------------------------
	
	public Charset getCharset(){
		return charset;
	}
	
	private void setCharset(Charset charset){
		this.charset = charset;
	}
	
	public File getFile(){
		return inputFile;
	}
	
	
	//------- Methods for setting up the file reader -----------------------------------------
	
	private void initialize(String fileName) throws IOException{
		prepareFile(fileName);
		prepareReader();
	}
	
	protected void prepareFile(String fileName) throws IOException{
		inputFile = new File(fileName);
		if(inputFile.isDirectory())
			throw new IOException("I/O Error on opening file: File is a directory!");
		if(!inputFile.exists())
			throw new IOException("I/O Error on opening file: File does not exist!");
		if(!inputFile.canRead())
			throw new IOException("I/O Error on opening file: Unable to read file!");
	}
	
	protected void prepareReader() throws IOException{
		input = new BufferedReader(new InputStreamReader(new FileInputStream(inputFile), charset));
		adjustSystemProperties();
	}
	
	protected void adjustSystemProperties() throws IOException{
		systemLineSeparatorBackup = System.getProperty("line.separator");
		@SuppressWarnings("resource")
		InputStreamReader reader = new InputStreamReader(new FileInputStream(inputFile), charset);
		String lineSeparator = null;
		int next;
		while(lineSeparator == null && (next = reader.read()) != -1){
			char nextChar = (char) next;
			if(nextChar == '\n'){
				lineSeparator = "\n";
				break;
			} else if(nextChar == '\r'){
				lineSeparator = "\r";
				next = reader.read();
				if(next != -1 && ((char) next) == '\n'){
					lineSeparator += "\n";
				}
				break;
			}
		}
		if(lineSeparator != null){
			System.setProperty("line.separator", lineSeparator);
		}
	}
	
	protected void restoreSystemProperties(){
		System.setProperty("line.separator", systemLineSeparatorBackup);
	}
	
	
	//------- Functionality ------------------------------------------------------------------
	
	public String readLine() throws IOException{
		return input.readLine();
	}
	
	public void closeFile() throws IOException{
		input.close();
		restoreSystemProperties();
	}
	
	
	public static void main(String[] args) throws Exception{
		FileReader reader = new FileReader("NewFile.txt", Charset.forName("MacRoman"));
		String nextLine;
		while((nextLine = reader.readLine()) != null){
			System.out.println(nextLine);
		}
	}

}