first commit

Semester 1/Programming 1/Java/examples/projects/chapter03/number-display/NumberDisplay.ctxt

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+#BlueJ class context
+comment0.params=rollOverLimit
+comment0.target=NumberDisplay(int)
+comment0.text=\n\ Constructor\ for\ objects\ of\ class\ NumberDisplay.\n\ Set\ the\ limit\ at\ which\ the\ display\ rolls\ over.\n
+comment1.params=
+comment1.target=int\ getValue()
+comment1.text=\n\ Return\ the\ current\ value.\n
+comment2.params=
+comment2.target=java.lang.String\ getDisplayValue()
+comment2.text=\n\ Return\ the\ display\ value\ (that\ is,\ the\ current\ value\ as\ a\ two-digit\n\ String.\ If\ the\ value\ is\ less\ than\ ten,\ it\ will\ be\ padded\ with\ a\ leading\n\ zero).\n
+comment3.params=replacementValue
+comment3.target=void\ setValue(int)
+comment3.text=\n\ Set\ the\ value\ of\ the\ display\ to\ the\ new\ specified\ value.\ If\ the\ new\n\ value\ is\ less\ than\ zero\ or\ over\ the\ limit,\ do\ nothing.\n
+comment4.params=
+comment4.target=void\ increment()
+comment4.text=\n\ Increment\ the\ display\ value\ by\ one,\ rolling\ over\ to\ zero\ if\ the\n\ limit\ is\ reached.\n
+numComments=5

Semester 1/Programming 1/Java/examples/projects/chapter03/number-display/NumberDisplay.java

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+
+/**
+ * The NumberDisplay class represents a digital number display that can hold
+ * values from zero to a given limit. The limit can be specified when creating
+ * the display. The values range from zero (inclusive) to limit-1. If used,
+ * for example, for the seconds on a digital clock, the limit would be 60, 
+ * resulting in display values from 0 to 59. When incremented, the display 
+ * automatically rolls over to zero when reaching the limit.
+ * 
+ * @author Michael Kölling and David J. Barnes
+ * @version 2016.02.29
+ */
+public class NumberDisplay
+{
+    private int limit;
+    private int value;
+
+    /**
+     * Constructor for objects of class NumberDisplay.
+     * Set the limit at which the display rolls over.
+     */
+    public NumberDisplay(int rollOverLimit)
+    {
+        limit = rollOverLimit;
+        value = 0;
+    }
+
+    /**
+     * Return the current value.
+     */
+    public int getValue()
+    {
+        return value;
+    }
+
+    /**
+     * Return the display value (that is, the current value as a two-digit
+     * String. If the value is less than ten, it will be padded with a leading
+     * zero).
+     */
+    public String getDisplayValue()
+    {
+        if(value < 10) {
+            return "0" + value;
+        }
+        else {
+            return "" + value;
+        }
+    }
+
+    /**
+     * Set the value of the display to the new specified value. If the new
+     * value is less than zero or over the limit, do nothing.
+     */
+    public void setValue(int replacementValue)
+    {
+        if((replacementValue >= 0) && (replacementValue < limit)) {
+            value = replacementValue;
+        }
+    }
+
+    /**
+     * Increment the display value by one, rolling over to zero if the
+     * limit is reached.
+     */
+    public void increment()
+    {
+        value = (value + 1) % limit;
+    }
+}

Semester 1/Programming 1/Java/examples/projects/chapter03/number-display/README.TXT

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+Project: number-display
+Authors: Michael Kölling and David J. Barnes
+
+This project is part of the material for the book
+
+   Objects First with Java - A Practical Introduction using BlueJ
+   Sixth edition
+   David J. Barnes and Michael Kölling
+   Pearson Education, 2016
+
+It is discussed in chapter 3.
+
+To use this project, create an instance of class NumberDisplay. Then inspect this 
+instance and leave the inspector window open. With the inspector window open, 
+call the object's methods, such as increment and setValue.

Semester 1/Programming 1/Java/examples/projects/chapter03/number-display/package.bluej

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+#BlueJ package file
+objectbench.height=153
+objectbench.width=786
+package.editor.height=357
+package.editor.width=678
+package.editor.x=70
+package.editor.y=80
+package.numDependencies=0
+package.numTargets=1
+package.showExtends=true
+package.showUses=true
+project.charset=UTF-8
+readme.editor.height=626
+readme.editor.width=875
+readme.editor.x=53
+readme.editor.y=28
+target1.editor.height=796
+target1.editor.width=873
+target1.editor.x=234
+target1.editor.y=217
+target1.height=60
+target1.name=NumberDisplay
+target1.naviview.expanded=true
+target1.showInterface=false
+target1.type=ClassTarget
+target1.typeParameters=
+target1.width=110
+target1.x=210
+target1.y=100