Changes between Version 7 and Version 8 of ControlSystems/SoftwareTeam/Training/GettingStarted/IntroJava

Timestamp:

Oct 1, 2019, 9:58:09 PM (6 years ago)

Author:

David Albert

Comment:

--

ControlSystems/SoftwareTeam/Training/GettingStarted/IntroJava

@@ -58 +58 @@
 8. Press the Continue tool [[Image(continue.jpg)]] (or function key F5) above the editor window to allow the program to continue running to the end.  Observe the value printed in the output terminal window.
 
+== Conditionals
+Programs need to be able to react differently to varying data.  Conditional statements let us do this.  For example, a robot must be able to monitor its sensors to prevent collisions.  Consider (and try running) the following program:
+{{{
+public class ConditionalExample {
+    public static void main(String args[]) {
+        int rangeInInches;
+
+        rangeInInches = 10;
+
+        if (rangeInInches < 20) {
+           System.out.println("stop motors so we don't crash!");
+        } else {
+           System.out.println("full speed ahead!");
+        }
+    }
+}
+}}}
+* Save the program as ConditionalExample.java (notice how the name of the file must match the name of the class)
+* Run the program using the debugger with a breakpoint set on the first executable line (rangeInInches=10); step through the program using the stepover tool and observe the flow of the program.
+* What happens if you change the values stored in the variable rangeInInches to 25?
+
+== Loops
+It's also important for a program to be able to do things repeatedly; for example, the robot must read its sensors repeatedly and react only when certain conditions are met.  Consider (and try running) the following program:
+{{{
+public class LoopExample {
+    public static void main(String args[]) {
+        int counter;  
+
+        counter = 1;
+        while (counter <= 10) {
+            System.out.println(counter);
+            counter = counter + 1;
+        }
+    }
+}
+}}}
+* Save this program as Loop Example
+* Run the program in the debugger with a breakpoint set at the line while (counter <= 10)
+* Step through the program a line at a time, observing the program output, variables, and flow of execution
+
 == Princeton Java
 There's a lot to programming and you'll get to the fun stuff a lot faster if you do some self-study.  There are many Java tutorials, but if you'd like to try learning the Princeton way, try [https://introcs.cs.princeton.edu/java/home/ this one].