ReadHeaders.java Source code

Introduction

Here is the source code for ReadHeaders.java

Source

/*
 * Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
 * All rights reserved. Software written by Ian F. Darwin and others.
 * $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Java, the Duke mascot, and all variants of Sun's Java "steaming coffee
 * cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
 * pioneering role in inventing and promulgating (and standardizing) the Java 
 * language and environment is gratefully acknowledged.
 * 
 * The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
 * inventing predecessor languages C and C++ is also gratefully acknowledged.
 */

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;

import javax.mail.Header;

/**
 * Read a file return mail headers one at a time.
 */
public class ReadHeaders {
    protected BufferedReader is;

    /** Construct */
    public ReadHeaders(BufferedReader f) {
        is = f;
    }

    /** Main program showing how to use it */
    public static void main(String[] av) {
        switch (av.length) {
        case 0:
            ReadHeaders r = new ReadHeaders(new BufferedReader(new InputStreamReader(System.in)));
            printit(r);
            break;
        default:
            for (int i = 0; i < av.length; i++)
                try {
                    ReadHeaders rr = new ReadHeaders(new BufferedReader(new FileReader(av[i])));
                    printit(rr);
                } catch (FileNotFoundException e) {
                    System.err.println(e);
                }
            break;
        }
    }

    /** Simple demo showing how to use it */
    public static void printit(ReadHeaders r) {
        while (r.more()) {
            Header h = r.next();
            System.out.println(h.getValue());
        }
    }

    String inputLine;

    /** check to see if more headers available */
    public boolean more() {
        if (is == null)
            return false;
        try {

            inputLine = is.readLine();
            if (inputLine == null || inputLine.length() == 0) {
                is.close();
                is = null;
            }
        } catch (IOException e) {
            System.out.println("IOException: " + e);
            is = null;
            return false;
        }
        return true;
    }

    public Header next() {
        int pos = inputLine.indexOf(":");
        if (pos < 0)
            return new Header("??", inputLine);
        return new Header(inputLine.substring(0, pos), inputLine.substring(pos + 1));
    }
}