PC Online 1998 January/PCO0198.ISO/1&1/java.z/java_301/java/net/URL.class

Java Class File | 1996-10-20 | 6.1 KB | 209 lines

package java.net;

import java.io.IOException;
import java.io.InputStream;
import java.util.Hashtable;

public final class URL {
   private String protocol;
   private String host;
   private int port;
   private String file;
   private String ref;
   URLStreamHandler handler;
   static URLStreamHandlerFactory factory;
   static Hashtable handlers = new Hashtable();

   public URL(String protocol, String host, int port, String file) throws MalformedURLException {
      this.port = -1;
      this.protocol = protocol;
      this.host = host;
      this.file = file;
      this.port = port;
      if ((this.handler = getURLStreamHandler(protocol)) == null) {
         throw new MalformedURLException("unknown protocol: " + protocol);
      }
   }

   public URL(String protocol, String host, String file) throws MalformedURLException {
      this(protocol, host, -1, file);
   }

   public URL(String spec) throws MalformedURLException {
      this((URL)null, spec);
   }

   public URL(URL context, String spec) throws MalformedURLException {
      this.port = -1;
      String original = spec;
      int start = 0;
      String newProtocol = null;

      try {
         int limit;
         for(limit = spec.length(); limit > 0 && spec.charAt(limit - 1) <= ' '; --limit) {
         }

         while(start < limit && spec.charAt(start) <= ' ') {
            ++start;
         }

         if (spec.regionMatches(true, start, "url:", 0, 4)) {
            start += 4;
         }

         int c;
         for(int i = start; i < limit && (c = spec.charAt(i)) != 47; ++i) {
            if (c == 58) {
               newProtocol = spec.substring(start, i).toLowerCase();
               start = i + 1;
               break;
            }
         }

         if (context == null || newProtocol != null && !newProtocol.equals(context.protocol)) {
            this.protocol = newProtocol;
         } else {
            this.protocol = context.protocol;
            this.host = context.host;
            this.port = context.port;
            this.file = context.file;
         }

         if (this.protocol == null) {
            throw new MalformedURLException("no protocol: " + original);
         } else if ((this.handler = getURLStreamHandler(this.protocol)) == null) {
            throw new MalformedURLException("unknown protocol: " + this.protocol);
         } else {
            int var12 = spec.indexOf(35, start);
            if (var12 >= 0) {
               this.ref = spec.substring(var12 + 1, limit);
               limit = var12;
            }

            this.handler.parseURL(this, spec, start, limit);
         }
      } catch (MalformedURLException e) {
         throw e;
      } catch (Exception e) {
         throw new MalformedURLException(spec + ": " + e);
      }
   }

   protected void set(String protocol, String host, int port, String file, String ref) {
      this.protocol = protocol;
      this.host = host;
      this.port = port;
      this.file = file;
      this.ref = ref;
   }

   public int getPort() {
      return this.port;
   }

   public String getProtocol() {
      return this.protocol;
   }

   public String getHost() {
      return this.host;
   }

   public String getHostAddress() throws UnknownHostException {
      return InetAddress.getByName(this.host).getHostAddress();
   }

   public String getFile() {
      return this.file;
   }

   public String getRef() {
      return this.ref;
   }

   public boolean equals(Object obj) {
      return obj instanceof URL && this.sameFile((URL)obj);
   }

   public int hashCode() {
      return this.protocol.hashCode() ^ this.host.hashCode() ^ this.file.hashCode();
   }

   boolean hostsEqual(String h1, String h2) {
      if (h1.equals(h2)) {
         return true;
      } else {
         try {
            InetAddress a1 = InetAddress.getByName(h1);
            InetAddress a2 = InetAddress.getByName(h2);
            return a1.equals(a2);
         } catch (UnknownHostException var5) {
         } catch (SecurityException var6) {
         }

         return false;
      }
   }

   public boolean sameFile(URL other) {
      return this.protocol.equals(other.protocol) && this.hostsEqual(this.host, other.host) && this.port == other.port && this.file.equals(other.file);
   }

   public String toString() {
      return this.toExternalForm();
   }

   public String toExternalForm() {
      return this.handler.toExternalForm(this);
   }

   public URLConnection openConnection() throws IOException {
      return this.handler.openConnection(this);
   }

   public final InputStream openStream() throws IOException {
      return this.openConnection().getInputStream();
   }

   public final Object getContent() throws IOException {
      return this.openConnection().getContent();
   }

   public static synchronized void setURLStreamHandlerFactory(URLStreamHandlerFactory fac) {
      if (factory != null) {
         throw new Error("factory already defined");
      } else {
         SecurityManager security = System.getSecurityManager();
         if (security != null) {
            security.checkSetFactory();
         }

         factory = fac;
      }
   }

   static synchronized URLStreamHandler getURLStreamHandler(String protocol) {
      URLStreamHandler handler = (URLStreamHandler)handlers.get(protocol);
      if (handler == null) {
         if (factory != null) {
            handler = factory.createURLStreamHandler(protocol);
         }

         if (handler == null) {
            try {
               String clname = "sun.net.www.protocol." + protocol + ".Handler";
               handler = (URLStreamHandler)Class.forName(clname).newInstance();
            } catch (Exception var3) {
            }
         }

         if (handler != null) {
            handlers.put(protocol, handler);
         }
      }

      return handler;
   }
}