001package com.pusher.client.connection;
002
003/**
004 * Represents a change in connection state.
005 */
006public class ConnectionStateChange {
007
008    private final ConnectionState previousState;
009    private final ConnectionState currentState;
010
011    /**
012     * Used within the library to create a connection state change. Not be used
013     * used as part of the API.
014     *
015     * @param previousState The previous connection state
016     * @param currentState The current connection state
017     */
018    public ConnectionStateChange(final ConnectionState previousState, final ConnectionState currentState) {
019
020        if (previousState == currentState) {
021            throw new IllegalArgumentException(
022                    "Attempted to create an connection state update where both previous and current state are: "
023                            + currentState);
024        }
025
026        this.previousState = previousState;
027        this.currentState = currentState;
028    }
029
030    /**
031     * The previous connections state. The state the connection has transitioned
032     * from.
033     *
034     * @return The previous connection state
035     */
036    public ConnectionState getPreviousState() {
037        return previousState;
038    }
039
040    /**
041     * The current connection state. The state the connection has transitioned
042     * to.
043     *
044     * @return The current connection state
045     */
046    public ConnectionState getCurrentState() {
047        return currentState;
048    }
049
050    @Override
051    public int hashCode() {
052        return previousState.hashCode() + currentState.hashCode();
053    }
054
055    @Override
056    public boolean equals(final Object obj) {
057        if (obj != null && obj instanceof ConnectionStateChange) {
058            final ConnectionStateChange other = (ConnectionStateChange)obj;
059            return currentState == other.currentState && previousState == other.previousState;
060        }
061
062        return false;
063    }
064}