www.pudn.com > jnp-src.rar > HttpInputStream.java

/*
 * Java Network Programming, Second Edition
 * Merlin Hughes, Michael Shoffner, Derek Hamner
 * Manning Publications Company; ISBN 188477749X
 *
 * http://nitric.com/jnp/
 *
 * Copyright (c) 1997-1999 Merlin Hughes, Michael Shoffner, Derek Hamner;
 * all rights reserved; see license.txt for details.
 */

import java.io.*; 
import java.net.*; 
import java.util.*; 
 
public class HttpInputStream extends BufferedInputStream { 
  public HttpInputStream (InputStream in) { 
    super (in); 
  } 
 
  protected String method, path, queryString; 
  protected float version; 
  protected Hashtable headers = new Hashtable (); 
 
  public void readRequest () throws IOException { 
    String request = readLine (); 
    if (request == null) 
      throw new HttpException (HTTP.STATUS_BAD_REQUEST, "Null query"); 
    StringTokenizer parts = new StringTokenizer (request); 
    try { 
      parseMethod (parts.nextToken ()); 
      parseRequest (parts.nextToken ()); 
    } catch (NoSuchElementException ex) { 
      throw new HttpException (HTTP.STATUS_BAD_REQUEST, request); 
    } 
    if (parts.hasMoreTokens ()) 
      parseVersion (parts.nextToken ()); 
    else 
      version = 0.9f; 
    if ((version < 1.0f) && (method == HTTP.METHOD_HEAD)) 
      throw new HttpException (HTTP.STATUS_NOT_ALLOWED, method); 
    if (version >= 1.0f) 
      readHeaders (); 
  } 
 
  protected void parseMethod (String method) throws HttpException { 
    if (method.equals (HTTP.METHOD_GET)) 
      this.method = HTTP.METHOD_GET; 
    else if (method.equals (HTTP.METHOD_POST)) 
      this.method = HTTP.METHOD_POST; 
    else if (method.equals (HTTP.METHOD_HEAD)) 
      this.method = HTTP.METHOD_HEAD; 
    else 
      throw new HttpException (HTTP.STATUS_NOT_IMPLEMENTED, method); 
  } 
 
  protected void parseRequest (String request) throws HttpException { 
    if (!request.startsWith ("/")) 
      throw new HttpException (HTTP.STATUS_BAD_REQUEST, request); 
    int queryIdx = request.indexOf ('?'); 
    if (queryIdx == -1) { 
      path = HTTP.canonicalizePath (request); 
      queryString = ""; 
    } else { 
      path = HTTP.canonicalizePath (request.substring (0, queryIdx)); 
      queryString = request.substring (queryIdx + 1); 
    } 
  } 
 
  protected void parseVersion (String verStr) throws HttpException { 
    if (!verStr.startsWith ("HTTP/")) 
      throw new HttpException (HTTP.STATUS_BAD_REQUEST, verStr); 
    try { 
      version = Float.valueOf (verStr.substring (5)).floatValue (); 
    } catch (NumberFormatException ex) { 
      throw new HttpException (HTTP.STATUS_BAD_REQUEST, verStr); 
    } 
  } 
 
  protected void readHeaders () throws IOException { 
    String header; 
    while (((header = readLine ()) != null) && !header.equals ("")) { 
      int colonIdx = header.indexOf (':'); 
      if (colonIdx != -1) { 
        String name = header.substring (0, colonIdx); 
        String value = header.substring (colonIdx + 1); 
        headers.put (name.toLowerCase (), value.trim ()); 
      } 
    } 
  } 
 
  public String readLine () throws IOException { 
    StringBuffer line = new StringBuffer (); 
    int c; 
    while (((c = read ()) != -1) && (c != '\n') && (c != '\r')) 
      line.append ((char) c); 
    if ((c == '\r') && ((c = read ()) != '\n') && (c != -1)) 
      -- pos; 
    return ((c == -1) && (line.length () == 0)) ? null : line.toString (); 
  } 
 
  public String getMethod () { 
    return method; 
  } 
 
  public String getPath () { 
    return path; 
  } 
 
  public String getQueryString () { 
    return queryString; 
  } 
 
  public float getVersion () { 
    return version; 
  } 
 
  public String getHeader (String name) { 
    return (String) headers.get (name.toLowerCase ()); 
  } 
 
  public Enumeration getHeaderNames () { 
    return headers.keys (); 
  } 
}