jdk/src/share/classes/java/net/URLStreamHandler.java
changeset 2 90ce3da70b43
child 5506 202f599c92aa
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/net/URLStreamHandler.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,590 @@
+/*
+ * Copyright 1995-2006 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code 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
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.net;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.File;
+import java.io.OutputStream;
+import java.util.Hashtable;
+import sun.net.util.IPAddressUtil;
+import sun.net.www.ParseUtil;
+
+/**
+ * The abstract class <code>URLStreamHandler</code> is the common
+ * superclass for all stream protocol handlers. A stream protocol
+ * handler knows how to make a connection for a particular protocol
+ * type, such as <code>http</code>, <code>ftp</code>, or
+ * <code>gopher</code>.
+ * <p>
+ * In most cases, an instance of a <code>URLStreamHandler</code>
+ * subclass is not created directly by an application. Rather, the
+ * first time a protocol name is encountered when constructing a
+ * <code>URL</code>, the appropriate stream protocol handler is
+ * automatically loaded.
+ *
+ * @author  James Gosling
+ * @see     java.net.URL#URL(java.lang.String, java.lang.String, int, java.lang.String)
+ * @since   JDK1.0
+ */
+public abstract class URLStreamHandler {
+    /**
+     * Opens a connection to the object referenced by the
+     * <code>URL</code> argument.
+     * This method should be overridden by a subclass.
+     *
+     * <p>If for the handler's protocol (such as HTTP or JAR), there
+     * exists a public, specialized URLConnection subclass belonging
+     * to one of the following packages or one of their subpackages:
+     * java.lang, java.io, java.util, java.net, the connection
+     * returned will be of that subclass. For example, for HTTP an
+     * HttpURLConnection will be returned, and for JAR a
+     * JarURLConnection will be returned.
+     *
+     * @param      u   the URL that this connects to.
+     * @return     a <code>URLConnection</code> object for the <code>URL</code>.
+     * @exception  IOException  if an I/O error occurs while opening the
+     *               connection.
+     */
+    abstract protected URLConnection openConnection(URL u) throws IOException;
+
+    /**
+     * Same as openConnection(URL), except that the connection will be
+     * made through the specified proxy; Protocol handlers that do not
+     * support proxying will ignore the proxy parameter and make a
+     * normal connection.
+     *
+     * Calling this method preempts the system's default ProxySelector
+     * settings.
+     *
+     * @param      u   the URL that this connects to.
+     * @param      p   the proxy through which the connection will be made.
+     *                 If direct connection is desired, Proxy.NO_PROXY
+     *                 should be specified.
+     * @return     a <code>URLConnection</code> object for the <code>URL</code>.
+     * @exception  IOException  if an I/O error occurs while opening the
+     *               connection.
+     * @exception  IllegalArgumentException if either u or p is null,
+     *               or p has the wrong type.
+     * @exception  UnsupportedOperationException if the subclass that
+     *               implements the protocol doesn't support this method.
+     * @since      1.5
+     */
+    protected URLConnection openConnection(URL u, Proxy p) throws IOException {
+        throw new UnsupportedOperationException("Method not implemented.");
+    }
+
+    /**
+     * Parses the string representation of a <code>URL</code> into a
+     * <code>URL</code> object.
+     * <p>
+     * If there is any inherited context, then it has already been
+     * copied into the <code>URL</code> argument.
+     * <p>
+     * The <code>parseURL</code> method of <code>URLStreamHandler</code>
+     * parses the string representation as if it were an
+     * <code>http</code> specification. Most URL protocol families have a
+     * similar parsing. A stream protocol handler for a protocol that has
+     * a different syntax must override this routine.
+     *
+     * @param   u       the <code>URL</code> to receive the result of parsing
+     *                  the spec.
+     * @param   spec    the <code>String</code> representing the URL that
+     *                  must be parsed.
+     * @param   start   the character index at which to begin parsing. This is
+     *                  just past the '<code>:</code>' (if there is one) that
+     *                  specifies the determination of the protocol name.
+     * @param   limit   the character position to stop parsing at. This is the
+     *                  end of the string or the position of the
+     *                  "<code>#</code>" character, if present. All information
+     *                  after the sharp sign indicates an anchor.
+     */
+    protected void parseURL(URL u, String spec, int start, int limit) {
+        // These fields may receive context content if this was relative URL
+        String protocol = u.getProtocol();
+        String authority = u.getAuthority();
+        String userInfo = u.getUserInfo();
+        String host = u.getHost();
+        int port = u.getPort();
+        String path = u.getPath();
+        String query = u.getQuery();
+
+        // This field has already been parsed
+        String ref = u.getRef();
+
+        boolean isRelPath = false;
+        boolean queryOnly = false;
+
+// FIX: should not assume query if opaque
+        // Strip off the query part
+        if (start < limit) {
+            int queryStart = spec.indexOf('?');
+            queryOnly = queryStart == start;
+            if ((queryStart != -1) && (queryStart < limit)) {
+                query = spec.substring(queryStart+1, limit);
+                if (limit > queryStart)
+                    limit = queryStart;
+                spec = spec.substring(0, queryStart);
+            }
+        }
+
+        int i = 0;
+        // Parse the authority part if any
+        boolean isUNCName = (start <= limit - 4) &&
+                        (spec.charAt(start) == '/') &&
+                        (spec.charAt(start + 1) == '/') &&
+                        (spec.charAt(start + 2) == '/') &&
+                        (spec.charAt(start + 3) == '/');
+        if (!isUNCName && (start <= limit - 2) && (spec.charAt(start) == '/') &&
+            (spec.charAt(start + 1) == '/')) {
+            start += 2;
+            i = spec.indexOf('/', start);
+            if (i < 0) {
+                i = spec.indexOf('?', start);
+                if (i < 0)
+                    i = limit;
+            }
+
+            host = authority = spec.substring(start, i);
+
+            int ind = authority.indexOf('@');
+            if (ind != -1) {
+                userInfo = authority.substring(0, ind);
+                host = authority.substring(ind+1);
+            } else {
+                userInfo = null;
+            }
+            if (host != null) {
+                // If the host is surrounded by [ and ] then its an IPv6
+                // literal address as specified in RFC2732
+                if (host.length()>0 && (host.charAt(0) == '[')) {
+                    if ((ind = host.indexOf(']')) > 2) {
+
+                        String nhost = host ;
+                        host = nhost.substring(0,ind+1);
+                        if (!IPAddressUtil.
+                            isIPv6LiteralAddress(host.substring(1, ind))) {
+                            throw new IllegalArgumentException(
+                                "Invalid host: "+ host);
+                        }
+
+                        port = -1 ;
+                        if (nhost.length() > ind+1) {
+                            if (nhost.charAt(ind+1) == ':') {
+                                ++ind ;
+                                // port can be null according to RFC2396
+                                if (nhost.length() > (ind + 1)) {
+                                    port = Integer.parseInt(nhost.substring(ind+1));
+                                }
+                            } else {
+                                throw new IllegalArgumentException(
+                                    "Invalid authority field: " + authority);
+                            }
+                        }
+                    } else {
+                        throw new IllegalArgumentException(
+                            "Invalid authority field: " + authority);
+                    }
+                } else {
+                    ind = host.indexOf(':');
+                    port = -1;
+                    if (ind >= 0) {
+                        // port can be null according to RFC2396
+                        if (host.length() > (ind + 1)) {
+                            port = Integer.parseInt(host.substring(ind + 1));
+                        }
+                        host = host.substring(0, ind);
+                    }
+                }
+            } else {
+                host = "";
+            }
+            if (port < -1)
+                throw new IllegalArgumentException("Invalid port number :" +
+                                                   port);
+            start = i;
+            // If the authority is defined then the path is defined by the
+            // spec only; See RFC 2396 Section 5.2.4.
+            if (authority != null && authority.length() > 0)
+                path = "";
+        }
+
+        if (host == null) {
+            host = "";
+        }
+
+        // Parse the file path if any
+        if (start < limit) {
+            if (spec.charAt(start) == '/') {
+                path = spec.substring(start, limit);
+            } else if (path != null && path.length() > 0) {
+                isRelPath = true;
+                int ind = path.lastIndexOf('/');
+                String seperator = "";
+                if (ind == -1 && authority != null)
+                    seperator = "/";
+                path = path.substring(0, ind + 1) + seperator +
+                         spec.substring(start, limit);
+
+            } else {
+                String seperator = (authority != null) ? "/" : "";
+                path = seperator + spec.substring(start, limit);
+            }
+        } else if (queryOnly && path != null) {
+            int ind = path.lastIndexOf('/');
+            if (ind < 0)
+                ind = 0;
+            path = path.substring(0, ind) + "/";
+        }
+        if (path == null)
+            path = "";
+
+        if (isRelPath) {
+            // Remove embedded /./
+            while ((i = path.indexOf("/./")) >= 0) {
+                path = path.substring(0, i) + path.substring(i + 2);
+            }
+            // Remove embedded /../ if possible
+            i = 0;
+            while ((i = path.indexOf("/../", i)) >= 0) {
+                /*
+                 * A "/../" will cancel the previous segment and itself,
+                 * unless that segment is a "/../" itself
+                 * i.e. "/a/b/../c" becomes "/a/c"
+                 * but "/../../a" should stay unchanged
+                 */
+                if (i > 0 && (limit = path.lastIndexOf('/', i - 1)) >= 0 &&
+                    (path.indexOf("/../", limit) != 0)) {
+                    path = path.substring(0, limit) + path.substring(i + 3);
+                    i = 0;
+                } else {
+                    i = i + 3;
+                }
+            }
+            // Remove trailing .. if possible
+            while (path.endsWith("/..")) {
+                i = path.indexOf("/..");
+                if ((limit = path.lastIndexOf('/', i - 1)) >= 0) {
+                    path = path.substring(0, limit+1);
+                } else {
+                    break;
+                }
+            }
+            // Remove starting .
+            if (path.startsWith("./") && path.length() > 2)
+                path = path.substring(2);
+
+            // Remove trailing .
+            if (path.endsWith("/."))
+                path = path.substring(0, path.length() -1);
+        }
+
+        setURL(u, protocol, host, port, authority, userInfo, path, query, ref);
+    }
+
+    /**
+     * Returns the default port for a URL parsed by this handler. This method
+     * is meant to be overidden by handlers with default port numbers.
+     * @return the default port for a <code>URL</code> parsed by this handler.
+     * @since 1.3
+     */
+    protected int getDefaultPort() {
+        return -1;
+    }
+
+    /**
+     * Provides the default equals calculation. May be overidden by handlers
+     * for other protocols that have different requirements for equals().
+     * This method requires that none of its arguments is null. This is
+     * guaranteed by the fact that it is only called by java.net.URL class.
+     * @param u1 a URL object
+     * @param u2 a URL object
+     * @return <tt>true</tt> if the two urls are
+     * considered equal, ie. they refer to the same
+     * fragment in the same file.
+     * @since 1.3
+     */
+    protected boolean equals(URL u1, URL u2) {
+        String ref1 = u1.getRef();
+        String ref2 = u2.getRef();
+        return (ref1 == ref2 || (ref1 != null && ref1.equals(ref2))) &&
+               sameFile(u1, u2);
+    }
+
+    /**
+     * Provides the default hash calculation. May be overidden by handlers for
+     * other protocols that have different requirements for hashCode
+     * calculation.
+     * @param u a URL object
+     * @return an <tt>int</tt> suitable for hash table indexing
+     * @since 1.3
+     */
+    protected int hashCode(URL u) {
+        int h = 0;
+
+        // Generate the protocol part.
+        String protocol = u.getProtocol();
+        if (protocol != null)
+            h += protocol.hashCode();
+
+        // Generate the host part.
+        InetAddress addr = getHostAddress(u);
+        if (addr != null) {
+            h += addr.hashCode();
+        } else {
+            String host = u.getHost();
+            if (host != null)
+                h += host.toLowerCase().hashCode();
+        }
+
+        // Generate the file part.
+        String file = u.getFile();
+        if (file != null)
+            h += file.hashCode();
+
+        // Generate the port part.
+        if (u.getPort() == -1)
+            h += getDefaultPort();
+        else
+            h += u.getPort();
+
+        // Generate the ref part.
+        String ref = u.getRef();
+        if (ref != null)
+            h += ref.hashCode();
+
+        return h;
+    }
+
+    /**
+     * Compare two urls to see whether they refer to the same file,
+     * i.e., having the same protocol, host, port, and path.
+     * This method requires that none of its arguments is null. This is
+     * guaranteed by the fact that it is only called indirectly
+     * by java.net.URL class.
+     * @param u1 a URL object
+     * @param u2 a URL object
+     * @return true if u1 and u2 refer to the same file
+     * @since 1.3
+     */
+    protected boolean sameFile(URL u1, URL u2) {
+        // Compare the protocols.
+        if (!((u1.getProtocol() == u2.getProtocol()) ||
+              (u1.getProtocol() != null &&
+               u1.getProtocol().equalsIgnoreCase(u2.getProtocol()))))
+            return false;
+
+        // Compare the files.
+        if (!(u1.getFile() == u2.getFile() ||
+              (u1.getFile() != null && u1.getFile().equals(u2.getFile()))))
+            return false;
+
+        // Compare the ports.
+        int port1, port2;
+        port1 = (u1.getPort() != -1) ? u1.getPort() : u1.handler.getDefaultPort();
+        port2 = (u2.getPort() != -1) ? u2.getPort() : u2.handler.getDefaultPort();
+        if (port1 != port2)
+            return false;
+
+        // Compare the hosts.
+        if (!hostsEqual(u1, u2))
+            return false;
+
+        return true;
+    }
+
+    /**
+     * Get the IP address of our host. An empty host field or a DNS failure
+     * will result in a null return.
+     *
+     * @param u a URL object
+     * @return an <code>InetAddress</code> representing the host
+     * IP address.
+     * @since 1.3
+     */
+    protected synchronized InetAddress getHostAddress(URL u) {
+        if (u.hostAddress != null)
+            return u.hostAddress;
+
+        String host = u.getHost();
+        if (host == null || host.equals("")) {
+            return null;
+        } else {
+            try {
+                u.hostAddress = InetAddress.getByName(host);
+            } catch (UnknownHostException ex) {
+                return null;
+            } catch (SecurityException se) {
+                return null;
+            }
+        }
+        return u.hostAddress;
+    }
+
+    /**
+     * Compares the host components of two URLs.
+     * @param u1 the URL of the first host to compare
+     * @param u2 the URL of the second host to compare
+     * @return  <tt>true</tt> if and only if they
+     * are equal, <tt>false</tt> otherwise.
+     * @since 1.3
+     */
+    protected boolean hostsEqual(URL u1, URL u2) {
+        InetAddress a1 = getHostAddress(u1);
+        InetAddress a2 = getHostAddress(u2);
+        // if we have internet address for both, compare them
+        if (a1 != null && a2 != null) {
+            return a1.equals(a2);
+        // else, if both have host names, compare them
+        } else if (u1.getHost() != null && u2.getHost() != null)
+            return u1.getHost().equalsIgnoreCase(u2.getHost());
+         else
+            return u1.getHost() == null && u2.getHost() == null;
+    }
+
+    /**
+     * Converts a <code>URL</code> of a specific protocol to a
+     * <code>String</code>.
+     *
+     * @param   u   the URL.
+     * @return  a string representation of the <code>URL</code> argument.
+     */
+    protected String toExternalForm(URL u) {
+
+        // pre-compute length of StringBuffer
+        int len = u.getProtocol().length() + 1;
+        if (u.getAuthority() != null && u.getAuthority().length() > 0)
+            len += 2 + u.getAuthority().length();
+        if (u.getPath() != null) {
+            len += u.getPath().length();
+        }
+        if (u.getQuery() != null) {
+            len += 1 + u.getQuery().length();
+        }
+        if (u.getRef() != null)
+            len += 1 + u.getRef().length();
+
+        StringBuffer result = new StringBuffer(len);
+        result.append(u.getProtocol());
+        result.append(":");
+        if (u.getAuthority() != null && u.getAuthority().length() > 0) {
+            result.append("//");
+            result.append(u.getAuthority());
+        }
+        if (u.getPath() != null) {
+            result.append(u.getPath());
+        }
+        if (u.getQuery() != null) {
+            result.append('?');
+            result.append(u.getQuery());
+        }
+        if (u.getRef() != null) {
+            result.append("#");
+            result.append(u.getRef());
+        }
+        return result.toString();
+    }
+
+    /**
+     * Sets the fields of the <code>URL</code> argument to the indicated values.
+     * Only classes derived from URLStreamHandler are supposed to be able
+     * to call the set method on a URL.
+     *
+     * @param   u         the URL to modify.
+     * @param   protocol  the protocol name.
+     * @param   host      the remote host value for the URL.
+     * @param   port      the port on the remote machine.
+     * @param   authority the authority part for the URL.
+     * @param   userInfo the userInfo part of the URL.
+     * @param   path      the path component of the URL.
+     * @param   query     the query part for the URL.
+     * @param   ref       the reference.
+     * @exception       SecurityException       if the protocol handler of the URL is
+     *                                  different from this one
+     * @see     java.net.URL#set(java.lang.String, java.lang.String, int, java.lang.String, java.lang.String)
+     * @since 1.3
+     */
+       protected void setURL(URL u, String protocol, String host, int port,
+                             String authority, String userInfo, String path,
+                             String query, String ref) {
+        if (this != u.handler) {
+            throw new SecurityException("handler for url different from " +
+                                        "this handler");
+        }
+        // ensure that no one can reset the protocol on a given URL.
+        u.set(u.getProtocol(), host, port, authority, userInfo, path, query, ref);
+    }
+
+    /**
+     * Sets the fields of the <code>URL</code> argument to the indicated values.
+     * Only classes derived from URLStreamHandler are supposed to be able
+     * to call the set method on a URL.
+     *
+     * @param   u         the URL to modify.
+     * @param   protocol  the protocol name. This value is ignored since 1.2.
+     * @param   host      the remote host value for the URL.
+     * @param   port      the port on the remote machine.
+     * @param   file      the file.
+     * @param   ref       the reference.
+     * @exception       SecurityException       if the protocol handler of the URL is
+     *                                  different from this one
+     * @deprecated Use setURL(URL, String, String, int, String, String, String,
+     *             String);
+     */
+    @Deprecated
+    protected void setURL(URL u, String protocol, String host, int port,
+                          String file, String ref) {
+        /*
+         * Only old URL handlers call this, so assume that the host
+         * field might contain "user:passwd@host". Fix as necessary.
+         */
+        String authority = null;
+        String userInfo = null;
+        if (host != null && host.length() != 0) {
+            authority = (port == -1) ? host : host + ":" + port;
+            int at = host.lastIndexOf('@');
+            if (at != -1) {
+                userInfo = host.substring(0, at);
+                host = host.substring(at+1);
+            }
+        }
+
+        /*
+         * Assume file might contain query part. Fix as necessary.
+         */
+        String path = null;
+        String query = null;
+        if (file != null) {
+            int q = file.lastIndexOf('?');
+            if (q != -1) {
+                query = file.substring(q+1);
+                path = file.substring(0, q);
+            } else
+                path = file;
+        }
+        setURL(u, protocol, host, port, authority, userInfo, path, query, ref);
+    }
+}