Ch. 10, Mediators

src/main/java/app/mediator/moveATub/MoveATub.java

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+package app.mediator.moveATub;
+
+/*
+ * Copyright (c) 2001, 2005. Steven J. Metsker.
+ * 
+ * Steve Metsker makes no representations or warranties about
+ * the fitness of this software for any particular purpose, 
+ * including the implied warranty of merchantability.
+ *
+ * Please use this software as you wish with the sole
+ * restriction that you may not claim that you wrote it.
+ */
+
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.util.*;
+import java.util.List;
+
+import javax.swing.*;
+import javax.swing.event.ListSelectionEvent;
+import javax.swing.event.ListSelectionListener;
+
+import com.oozinoz.ui.SwingFacade;
+import com.oozinoz.ui.UI;
+
+/**
+ * This class is partially refactored, with a method for each control. The
+ * next step will be to create a mediator class, factoring the action logic
+ * out of this class.
+ */
+public class MoveATub extends JPanel implements ListSelectionListener, ActionListener {
+    private static Hashtable tubMachine;
+
+    private List boxes;
+    private JList boxList;
+
+    private JList tubList;
+    private Object selectedTub;
+
+    private JList machineList;
+    private Object selectedMachine;
+
+    private JButton assignButton;
+
+    private UI ui = UI.NORMAL;
+
+    public static void main(String[] args) {
+        JFrame frame = SwingFacade.launch(new MoveATub(), "Move a Tub");
+        frame.setSize(600, 250);
+        frame.validate();
+    }
+
+    public MoveATub() {
+        super(new GridLayout(1, 4));
+        setFont(ui.getFont());
+
+        this.add(labeledPanel("From Machine...", boxList()));
+        this.add(labeledPanel("Move Tub...", tubList()));
+        this.add(labeledPanel("To Machine...", machineList()));
+        this.add(buttonPanel(assignButton()));
+    }
+
+    private Component buttonPanel(JButton button) {
+        JPanel result = new JPanel(new GridLayout(3, 1));
+        result.add(new JLabel(" "));
+
+        JPanel innerPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
+        innerPanel.add(button);
+        result.add(innerPanel);
+
+        result.add(new JLabel(" "));
+        return result;
+    }
+
+    private Component labeledPanel(String label, JList list) {
+        JPanel result = new JPanel(new BorderLayout());
+        result.add(new JLabel(label), BorderLayout.NORTH);
+        result.add(new JScrollPane(list), BorderLayout.CENTER);
+
+        int borderWidth = 15;
+        result.setBorder(BorderFactory.createEmptyBorder(borderWidth, borderWidth, borderWidth, borderWidth));
+
+        return result;
+    }
+
+    // This is a temporary approach that has hard-coded literals
+    private List boxes() {
+        if (boxes == null) {
+            boxes = new ArrayList();
+            boxes.add("Mixer-2201");
+            boxes.add("Mixer-2202");
+            boxes.add("Fuser-2101");
+            boxes.add("StarPress-2401");
+            boxes.add("StarPress-2402");
+            boxes.add("Assembler-2301");
+        }
+        return boxes;
+    }
+
+    private JList boxList() {
+        if (boxList == null) {
+            boxList = ui.createList(boxes().toArray());
+            boxList.addListSelectionListener(this);
+        }
+        return boxList;
+    }
+
+    private JList machineList() {
+        if (machineList == null) {
+            machineList = ui.createList(boxes().toArray());
+            machineList.addListSelectionListener(this);
+        }
+        return machineList;
+    }
+
+    private JList tubList() {
+        if (tubList == null) {
+            tubList = ui.createList(new String[] {});
+            tubList.addListSelectionListener(this);
+        }
+        return tubList;
+    }
+
+    private JButton assignButton() {
+        if (assignButton == null) {
+            assignButton = new JButton("Do it!");
+            assignButton.setEnabled(false);
+            assignButton.addActionListener(this);
+        }
+        return assignButton;
+    }
+
+    private static Hashtable tubMachine() {
+        if (tubMachine == null) {
+            tubMachine = new Hashtable();
+            tubMachine.put("T502", "Mixer-2201");
+            tubMachine.put("T503", "Mixer-2201");
+            tubMachine.put("T504", "Mixer-2201");
+            tubMachine.put("T101", "StarPress-2402");
+            tubMachine.put("T102", "StarPress-2402");
+        }
+        return tubMachine;
+    }
+
+    private static List tubNames(String machineName) {
+        ArrayList result = new ArrayList();
+
+        Enumeration iter = tubMachine().keys();
+        while (iter.hasMoreElements()) {
+            String key = iter.nextElement().toString();
+            String value = tubMachine().get(key).toString();
+            if (value.equals(machineName)) result.add(key);
+        }
+
+        return result;
+    }
+
+    private void updateTubList(String machineName) {
+        List tubs = tubNames(machineName);
+        tubList().setListData(tubs.toArray());
+    }
+
+    public void valueChanged(ListSelectionEvent e) {
+        JList sender = (JList) e.getSource();
+
+        if (!sender.isSelectionEmpty()) {
+            if (sender.equals(boxList())) 
+                updateTubList(sender.getSelectedValue().toString());
+
+            if (sender.equals(machineList())) 
+                selectedMachine = sender.getSelectedValue();
+
+            if (sender.equals(tubList())) 
+                selectedTub = sender.getSelectedValue();
+        }
+
+        assignButton().setEnabled(
+                !tubList().isSelectionEmpty() && !machineList().isSelectionEmpty());
+    }
+
+    public void actionPerformed(ActionEvent e) {
+        if (selectedMachine == null || selectedTub == null) return;
+        String tubName = selectedTub.toString();
+        String fromMachineName = (String) tubMachine().get(tubName);
+        String toMachineName = selectedMachine.toString();
+        tubMachine().put(tubName, toMachineName);
+        updateTubList(fromMachineName);
+        assignButton().setEnabled(false);
+    }
+}

src/main/java/app/mediator/moveATub2/MoveATub2.java

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+package app.mediator.moveATub2;
+
+import java.awt.BorderLayout;
+import java.awt.Component;
+import java.awt.FlowLayout;
+import java.awt.GridLayout;
+
+import javax.swing.BorderFactory;
+import javax.swing.JButton;
+import javax.swing.JFrame;
+import javax.swing.JLabel;
+import javax.swing.JList;
+import javax.swing.JPanel;
+import javax.swing.JScrollPane;
+
+import com.oozinoz.ui.SwingFacade;
+import com.oozinoz.ui.UI;
+
+/**
+ * Refactored from MoveATub. Challenges 10.1 and 10.2 we exercised on what would
+ * change, but didn't ask for an implementation.
+ * @author bostond
+ *
+ */
+
+public class MoveATub2 extends JPanel {
+
+	private static final long serialVersionUID = 8462238486128857207L;
+
+	private JButton assignButton;
+
+	private JList boxList;
+	private JList tubList;
+	private JList machineList; 
+
+    private UI ui = UI.NORMAL;
+
+    private NameBase data = new NameBase();
+    private MoveATubMediator mediator;
+
+    public static void main(String[] args) {
+        JFrame frame = SwingFacade.launch(new MoveATub2(), "Move a Tub2");
+        frame.setSize(600, 250);
+        frame.validate();
+    }
+
+    public MoveATub2() {
+        super(new GridLayout(1, 4));
+        setFont(ui.getFont());
+
+        this.mediator = new MoveATubMediator(this, data);
+
+        this.add(labeledPanel("From Machine...", boxList()));
+        this.add(labeledPanel("Move Tub...", tubList()));
+        this.add(labeledPanel("To Machine...", machineList()));
+        this.add(buttonPanel(assignButton()));
+    }
+
+    private Component buttonPanel(JButton button) {
+        JPanel result = new JPanel(new GridLayout(3, 1));
+        result.add(new JLabel(" "));
+
+        JPanel innerPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
+        innerPanel.add(button);
+        result.add(innerPanel);
+
+        result.add(new JLabel(" "));
+        return result;
+    }
+
+    private Component labeledPanel(String label, JList list) {
+        JPanel result = new JPanel(new BorderLayout());
+        result.add(new JLabel(label), BorderLayout.NORTH);
+        result.add(new JScrollPane(list), BorderLayout.CENTER);
+
+        int borderWidth = 15;
+        result.setBorder(BorderFactory.createEmptyBorder(borderWidth, borderWidth, borderWidth, borderWidth));
+
+        return result;
+    }
+
+	public JButton assignButton() {
+		if (assignButton == null) {
+            assignButton = new JButton("Do it!");
+            assignButton.setEnabled(false);
+        }
+        return assignButton;
+	}
+
+	public JList boxList() {
+        if (boxList == null) {
+            boxList = ui.createList(data.boxes());
+        }
+        return boxList;
+	}
+
+	public JList machineList() {
+        if (machineList == null) {
+        	machineList = ui.createList(data.boxes());
+        }
+        return machineList;
+	}
+
+    public JList tubList() {
+        if (tubList == null) {
+            tubList = ui.createList(new String[] {});
+        }
+        return tubList;
+    }
+
+}