Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright (C) 2010-12  Ciaran Gultnieks, ciaran@ciarang.com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 3
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

import java.io.Closeable;
import java.io.File;

import java.io.FileReader;
import java.io.IOException;

public class Main {
    public static int countSubstringOccurrence(File file, String substring) throws IOException {
        int count = 0;
        FileReader input = null;
        try {
            int currentSubstringIndex = 0;
            char[] buffer = new char[4096];

            input = new FileReader(file);
            int numRead = input.read(buffer);
            while (numRead != -1) {

                for (char c : buffer) {
                    if (c == substring.charAt(currentSubstringIndex)) {
                        currentSubstringIndex++;
                        if (currentSubstringIndex == substring.length()) {
                            count++;
                            currentSubstringIndex = 0;
                        }
                    } else {
                        currentSubstringIndex = 0;
                    }
                }
                numRead = input.read(buffer);
            }
        } finally {
            closeQuietly(input);
        }
        return count;
    }

    public static void closeQuietly(Closeable closeable) {
        if (closeable == null) {
            return;
        }
        try {
            closeable.close();
        } catch (IOException ioe) {
            // ignore
        }
    }
}