Host.java

/*******************************************************************************
 * Copyright 2011 Netflix
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package com.netflix.astyanax.connectionpool;

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.List;
import java.util.Set;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import com.google.common.collect.Lists;
import com.google.common.collect.Sets;

/**
 * Wrapper for the representation of the address for a cassandra node.  
 * This Host object is used by the connection pool to uniquely identify the host
 * and track it's connections.
 * 
 * @author elandau
 *
 */
public class Host implements Comparable<Host> {

    public static final Host NO_HOST = new Host();
    public static final String UKNOWN_RACK = "";
    
    private final String host;
    private final String ipAddress;
    private final int    port;
    private final String name;
    private final String url;
    private String       rack = UKNOWN_RACK;
    private String       id;
    private Set<String>  alternateIpAddress = Sets.newHashSet();
    private List<TokenRange> ranges = Lists.newArrayList();

    public static Pattern IP_ADDR_PATTERN = Pattern
            .compile("^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$");

    /**
     * Empty host used in error return codes
     */
    private Host() {
        this.host = "None";
        this.ipAddress = "0.0.0.0";
        this.port = 0;
        this.name = String.format("%s(%s):%d", this.host, this.ipAddress, this.port);
        this.url  = String.format("%s:%d", this.host, this.port);
    }

    /**
     * Construct a Host from a host:port combination.  The defaultPort is provided in case
     * the hostAndPort2 value does not have a port specified.
     * 
     * @param hostAndPort
     * @param defaultPort
     */
    public Host(String hostAndPort, int defaultPort) {

        String tempHost = parseHostFromHostAndPort(hostAndPort);
        this.port = parsePortFromHostAndPort(hostAndPort, defaultPort);

        Matcher match = IP_ADDR_PATTERN.matcher(tempHost);
        String workHost;
        String workIpAddress;
        if (match.matches()) {
            workHost      = tempHost;
            workIpAddress = tempHost;
        }
        else {
            try {
                InetAddress address = InetAddress.getByName(tempHost);
                workHost            = address.getHostName();
                workIpAddress       = address.getHostAddress();
            }
            catch (UnknownHostException e) {
                workHost      = tempHost;
                workIpAddress = tempHost;
            }
        }
        this.host      = workHost;
        this.ipAddress = workIpAddress;
        this.name      = String.format("%s(%s):%d", tempHost, this.ipAddress, this.port);
        this.url       = String.format("%s:%d", this.host, this.port);
    }

    /**
     * Parse the hostname from a "hostname:port" formatted string
     * 
     * @param hostAndPort
     * @return
     */
    public static String parseHostFromHostAndPort(String hostAndPort) {
        return hostAndPort.lastIndexOf(':') > 0 ? hostAndPort.substring(0, hostAndPort.lastIndexOf(':')) : hostAndPort;
    }

    /**
     * Parse the port from a "hostname:port" formatted string
     * 
     * @param urlPort
     * @param defaultPort
     * @return
     */
    public static int parsePortFromHostAndPort(String urlPort, int defaultPort) {
        return urlPort.lastIndexOf(':') > 0 ? Integer.valueOf(urlPort.substring(urlPort.lastIndexOf(':') + 1,
                urlPort.length())) : defaultPort;
    }

    @Override
    public String toString() {
        return name;
    }

    public boolean equals(Object obj) {
        if (!(obj instanceof Host)) {
            return false;
        }
        Host other = (Host) obj;
        return (other.host.equals(host) || other.ipAddress.equals(ipAddress)) && other.port == port;
    }

    public int hashCode() {
        return host.hashCode() + port;
    }

    public String getName() {
        return this.name;
    }

    public String getUrl() {
        return this.url;
    }

    public String getIpAddress() {
        return this.ipAddress;
    }

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

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

    public Set<String> getAlternateIpAddresses() {
        return this.alternateIpAddress;
    }

    public Host addAlternateIpAddress(String ipAddress) {
        this.alternateIpAddress.add(ipAddress);
        return this;
    }

    public String getId() {
        return this.id;
    }

    public Host setId(String id) {
        this.id = id;
        return this;
    }
    
    public Host setRack(String rack) {
        this.rack = rack;
        return this;
    }
    
    public String getRack() {
        return rack;
    }
 
    public synchronized Host setTokenRanges(List<TokenRange> ranges) {
        this.ranges = ranges;
        return this;
    }
    
    public synchronized List<TokenRange> getTokenRanges() {
        return this.ranges;
    }

    @Override
    public int compareTo(Host other) {
        int comp = this.host.compareTo(other.host);
        if (comp != 0) {
            comp = this.ipAddress.compareTo(other.ipAddress);
        }
        if (comp == 0) {
            comp = this.port - other.port;
        }
        return comp;
    }
}