split ch02

ChrisMayfield · ChrisMayfield · commit 01f9e08f5286 · 2020-06-17T13:15:40.000-04:00
diff --git a/ch02/DeclareAssign.java b/ch02/DeclareAssign.java
@@ -0,0 +1,23 @@
+public class DeclareAssign {
+
+    public static void main(String[] args) {
+        String message;
+        int x;
+
+        String firstName;
+        String lastName;
+        int hour, minute;
+
+        message = "Hello!";  // give message the value "Hello!"
+        hour = 11;           // assign the value 11 to hour
+        minute = 59;         // set minute to 59
+
+        message = "123";     // legal
+        // message = 123;    // not legal
+
+        String message2 = "Hello!";
+        int hour2 = 11;
+        int minute2 = 59;
+    }
+
+}
diff --git a/ch02/FloatingPoint.java b/ch02/FloatingPoint.java
@@ -0,0 +1,21 @@
+public class FloatingPoint {
+
+    public static void main(String[] args) {
+        double pi;
+        pi = 3.14159;
+
+        double minute3 = 59.0;
+        System.out.print("Fraction of the hour that has passed: ");
+        System.out.println(minute3 / 60.0);
+
+        double y = 1.0 / 3.0;  // correct
+
+        System.out.println(0.1 * 10);
+        System.out.println(0.1 + 0.1 + 0.1 + 0.1 + 0.1
+                         + 0.1 + 0.1 + 0.1 + 0.1 + 0.1);
+
+        double balance = 123.45;  // potential rounding error
+        int balance2 = 12345;     // total number of cents
+    }
+
+}
diff --git a/ch02/Hello.java b/ch02/Hello.java
@@ -0,0 +1,8 @@
+public class Hello {
+
+    public static void main(String[] args) {
+        System.out.println("Hello, ");
+        System.out.println("World!");
+    }
+
+}
diff --git a/ch02/MemoryDiagram.java b/ch02/MemoryDiagram.java
@@ -0,0 +1,10 @@
+public class MemoryDiagram {
+
+    public static void main(String[] args) {
+        int a = 5;
+        int b = a;     // a and b are now equal
+        a = 3;         // a and b are no longer equal
+        int c = 0;
+    }
+
+}
diff --git a/ch02/PrintingVars.java b/ch02/PrintingVars.java
@@ -0,0 +1,28 @@
+public class PrintingVars {
+
+    public static void main(String[] args) {
+        String firstLine = "Hello, again!";
+        System.out.println(firstLine);
+
+        System.out.print("The value of firstLine is ");
+        System.out.println(firstLine);
+
+        int hour = 11;
+        int minute = 59;
+        System.out.print("The current time is ");
+        System.out.print(hour);
+        System.out.print(":");
+        System.out.print(minute);
+        System.out.println(".");
+
+        System.out.print("Number of minutes since midnight: ");
+        System.out.println(hour * 60 + minute);
+
+        System.out.print("Fraction of the hour that has passed: ");
+        System.out.println(minute / 60);
+
+        System.out.print("Percent of the hour that has passed: ");
+        System.out.println(minute * 100 / 60);
+    }
+
+}
diff --git a/ch02/StringConcat.java b/ch02/StringConcat.java
@@ -0,0 +1,12 @@
+public class StringConcat {
+
+    public static void main(String[] args) {
+        System.out.println(1 + 2 + "Hello");
+        // the output is 3Hello
+
+        System.out.println("Hello" + 1 + 2);
+        // the output is Hello12
+
+    }
+
+}
diff --git a/ch02/Variables.java b/ch02/Variables.java
