BuggyDecoratorNode.java

package com.roboclub.robobuggy.nodes.baseNodes;

import com.roboclub.robobuggy.ros.Node;

/**
 * Abstract class that serves as the decorator specification in the decorator
 * pattern used to define buggy nodes
 *
 * @author Zachary Dawson
 */
public abstract class BuggyDecoratorNode implements BuggyNode {
    private String name;
    private BuggyNode node;

    /**
     * Creates a new decorator for the given {@link Node}
     *
     * @param node {@link Node} to decorate
     * @param name the name we want for this node to store so that it can be referenced later
     */
    public BuggyDecoratorNode(BuggyNode node, String name) {
        this.node = node;
        this.name = name;
    }

    /**
     * Set the base node after construction
     *
     * @param base {@link Node} to make the base node
     * @return the {@link Node} that was the old base node
     */
    public final Node setBaseNode(BuggyNode base) {
        Node oldBase = node;
        node = base;
        return oldBase;
    }

    /**
     * Starts the underlying {@link Node} and its decorator (in that order)
     * {@inheritDoc}
     */
    @Override
    public final boolean startNode() {
        boolean nodeStartResult = node.startNode();
        return nodeStartResult && startDecoratorNode();
    }

    /**
     * Shuts down the decorator and its underlying {@link Node} (in that order)
     * {@inheritDoc}
     */
    @Override
    public final boolean shutdown() {
        boolean nodeShutdownResult = node.shutdown();
        return shutdownDecoratorNode() && nodeShutdownResult;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public final void setNodeState(NodeState state) {
        node.setNodeState(state);
    }

    /**
     * Starts the decorator of the {@link Node}
     * Called after the {@link Node} being decorated is started
     *
     * @return true iff the decorator is started successfully
     */
    protected abstract boolean startDecoratorNode();

    /**
     * Shuts down the decorator of the {@link Node}
     * Called immediately before the {@link Node} being decorated is shut down
     *
     * @return true iff the decorator is shut down successfully
     */
    protected abstract boolean shutdownDecoratorNode();

    /**
     * used for updating the name by which this node is known
     *
     * @param newName the new name for this node
     */
    public void setName(String newName) {
        name = newName;
    }

    /**
     * gives access to the current value of this nodes name
     *
     * @return the name of this node
     */
    public String getName() {
        return name;
    }

}