aboutsummaryrefslogtreecommitdiff
path: root/libjava/classpath/java/rmi/server/UID.java
diff options
context:
space:
mode:
Diffstat (limited to 'libjava/classpath/java/rmi/server/UID.java')
-rw-r--r--libjava/classpath/java/rmi/server/UID.java225
1 files changed, 0 insertions, 225 deletions
diff --git a/libjava/classpath/java/rmi/server/UID.java b/libjava/classpath/java/rmi/server/UID.java
deleted file mode 100644
index 464d3d8..0000000
--- a/libjava/classpath/java/rmi/server/UID.java
+++ /dev/null
@@ -1,225 +0,0 @@
-/* UID.java -- The unique object Id
- Copyright (c) 2006 Free Software Foundation, Inc.
-
-This file is part of GNU Classpath.
-
-GNU Classpath 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 2, or (at your option)
-any later version.
-
-GNU Classpath 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 GNU Classpath; see the file COPYING. If not, write to the
-Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-02110-1301 USA.
-
-Linking this library statically or dynamically with other modules is
-making a combined work based on this library. Thus, the terms and
-conditions of the GNU General Public License cover the whole
-combination.
-
-As a special exception, the copyright holders of this library give you
-permission to link this library with independent modules to produce an
-executable, regardless of the license terms of these independent
-modules, and to copy and distribute the resulting executable under
-terms of your choice, provided that you also meet, for each linked
-independent module, the terms and conditions of the license of that
-module. An independent module is a module which is not derived from
-or based on this library. If you modify this library, you may extend
-this exception to your version of the library, but you are not
-obligated to do so. If you do not wish to do so, delete this
-exception statement from your version. */
-
-
-package java.rmi.server;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-import java.io.Serializable;
-import java.net.InetAddress;
-
-/**
- * Represents the unique identifier over time for the host which has generated
- * it. It contains time (when created), counter (the number of the UID
- * creation order) and virtual machine id components. The UID can also be
- * constructed specifying a "well known" identifier in the for of short:
- * this identifier defines the UID uniqueness alone.
- *
- * @author Audrius Meskauskas (audriusa@bioinformatics.org)
- */
-public final class UID
- implements Serializable
-{
- /**
- * Use the serial version uid for interoperability.
- */
- private static final long serialVersionUID = 1086053664494604050L;
-
- /**
- * The UID counter (the ordinary number in the sequence of number of UID's,
- * created during the recent millisecond). In the next millisecond, it
- * starts from the minimal value again. In the unlikely case of creating
- * more than 65536 uids per millisecond the process pauses till the next
- * ms.
- */
- private static short uidCounter = Short.MIN_VALUE;
-
- /**
- * The time, when the last UID has been created.
- */
- private static long last;
-
- /**
- * This constant tries to be the unique identifier of the virtual machine.
- */
- private static final int machineId = getMachineId();
-
- /**
- * The UID number in the UID creation sequence.
- */
- private short count;
-
- /**
- * Always gets the uniqueNr value.
- */
- private int unique;
-
- /**
- * The time stamp, when the UID was created.
- */
- private long time;
-
- /**
- * Create the new UID that would have the described features of the
- * uniqueness.
- */
- public UID()
- {
- synchronized (UID.class)
- {
- time = System.currentTimeMillis();
- unique = machineId;
- if (time > last)
- {
- last = time;
- count = uidCounter = Short.MIN_VALUE;
- }
- else
- {
- if (uidCounter == Short.MAX_VALUE)
- {
- // Make a 2 ms pause if the counter has reached the maximal
- // value. This should seldom happen.
- try
- {
- Thread.sleep(2);
- }
- catch (InterruptedException e)
- {
- }
- uidCounter = Short.MIN_VALUE;
- time = last = System.currentTimeMillis();
- }
- count = ++uidCounter;
- }
- }
- }
-
- /**
- * Create the new UID with the well known id (number). All UIDs, creates
- * with the this constructor having the same parameter are equal to each
- * other (regardless to the host and time where they were created.
- *
- * @param wellKnownId the well known UID.
- */
- public UID(short wellKnownId)
- {
- unique = wellKnownId;
- }
-
- /**
- * Get the hashCode of this UID.
- */
- public int hashCode()
- {
- return (int) (unique ^ time ^ count);
- }
-
- /**
- * Compare this UID with another UID for equality (not equal to other types of
- * objects).
- */
- public boolean equals(Object other)
- {
- if (other instanceof UID)
- {
- UID ui = (UID) other;
- return unique == ui.unique && time == ui.time && count == ui.count;
- }
- else
- return false;
- }
-
- public static UID read(DataInput in) throws IOException
- {
- UID uid = new UID();
- uid.unique = in.readInt();
- uid.time = in.readLong();
- uid.count = in.readShort();
- return (uid);
- }
-
- public void write(DataOutput out) throws IOException
- {
- out.writeInt(unique);
- out.writeLong(time);
- out.writeShort(count);
- }
-
- /**
- * Do our best to get the Id of this virtual machine.
- */
- static int getMachineId()
- {
- int hostIpHash;
-
- try
- {
- // Try to get the host IP.
- String host = InetAddress.getLocalHost().toString();
- // This hash is content - based, not the address based.
- hostIpHash = host.hashCode();
- }
- catch (Exception e)
- {
- // Failed due some reason.
- hostIpHash = 0;
- }
-
- // Should be the unque address if hashcodes are addresses.
- // Additionally, add the time when the RMI system was probably started
- // (this class was first instantiated).
- return new Object().hashCode() ^ (int) System.currentTimeMillis()
- ^ hostIpHash;
- }
-
- /**
- * Get the string representation of this UID.
- *
- * @return a string, uniquely identifying this id.
- */
- public String toString()
- {
- int max = Character.MAX_RADIX;
- // Translate into object count, counting from 0.
- long lc = (count - Short.MIN_VALUE) & 0xFFFF;
- return Long.toString(unique, max) + ":" + Long.toString(time, max) + "."
- + Long.toString(lc, max);
- }
-}