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-rw-r--r--java.html.markdown46
1 files changed, 35 insertions, 11 deletions
diff --git a/java.html.markdown b/java.html.markdown
index cdcf620c..b4624d5e 100644
--- a/java.html.markdown
+++ b/java.html.markdown
@@ -3,6 +3,7 @@
language: java
contributors:
- ["Jake Prather", "http://github.com/JakeHP"]
+ - ["Madison Dickson", "http://github.com/mix3d"]
filename: LearnJava.java
---
@@ -25,7 +26,8 @@ import java.util.ArrayList;
// Import all classes inside of java.security package
import java.security.*;
-// Each .java file contains one public class, with the same name as the file.
+// Each .java file contains one outer-level public class, with the same name as
+// the file.
public class LearnJava {
// A program must have a main method as an entry point
@@ -83,7 +85,7 @@ public class LearnJava {
// Char - A single 16-bit Unicode character
char fooChar = 'A';
- // Use final to make a variable immutable
+ // final variables can't be reassigned to another object
final int HOURS_I_WORK_PER_WEEK = 9001;
// Strings
@@ -98,7 +100,7 @@ public class LearnJava {
System.out.println(bazString);
// Arrays
- //The array size must be decided upon declaration
+ //The array size must be decided upon instantiation
//The format for declaring an array is follows:
//<datatype> [] <var name> = new <datatype>[<array size>];
int [] intArray = new int[10];
@@ -160,10 +162,13 @@ public class LearnJava {
// Incrementations
int i = 0;
System.out.println("\n->Inc/Dec-rementation");
- System.out.println(i++); //i = 1. Post-Incrementation
- System.out.println(++i); //i = 2. Pre-Incrementation
- System.out.println(i--); //i = 1. Post-Decrementation
- System.out.println(--i); //i = 0. Pre-Decrementation
+ // The ++ and -- operators increment and decrement by 1 respectively.
+ // If they are placed before the variable, they increment then return;
+ // after the variable they return then increment.
+ System.out.println(i++); //i = 1, prints 0 (post-increment)
+ System.out.println(++i); //i = 2, prints 2 (pre-increment)
+ System.out.println(i--); //i = 1, prints 2 (post-decrement)
+ System.out.println(--i); //i = 0, prints 0 (pre-decrement)
///////////////////////////////////////
// Control Structures
@@ -211,6 +216,18 @@ public class LearnJava {
}
System.out.println("fooFor Value: " + fooFor);
+ // For Each Loop
+ // An automatic iteration through an array or list of objects.
+ int[] fooList = {1,2,3,4,5,6,7,8,9};
+ //for each loop structure => for(<object> : <array_object>)
+ //reads as: for each object in the array
+ //note: the object type must match the array.
+
+ for( int bar : fooList ){
+ //System.out.println(bar);
+ //Iterates 9 times and prints 1-9 on new lines
+ }
+
// Switch Case
// A switch works with the byte, short, char, and int data types.
// It also works with enumerated types (discussed in Enum Types),
@@ -234,6 +251,13 @@ public class LearnJava {
}
System.out.println("Switch Case Result: " + monthString);
+ // Conditional Shorthand
+ // You can use the '?' operator for quick assignments or logic forks.
+ // Reads as "If (statement) is true, use <first value>, otherwise, use <second value>"
+ int foo = 5;
+ String bar = (foo < 10) ? "A" : "B";
+ System.out.println(bar); // Prints A, because the statement is true
+
///////////////////////////////////////
// Converting Data Types And Typcasting
@@ -274,14 +298,14 @@ public class LearnJava {
trek.speedUp(3); // You should always use setter and getter methods
trek.setCadence(100);
- // toString is a convention to display the value of this Object.
+ // toString returns this Object's string representation.
System.out.println("trek info: " + trek.toString());
} // End main method
} // End LearnJava class
-// You can include other, non-public classes in a .java file
+// You can include other, non-public outer-level classes in a .java file
// Class Declaration Syntax:
@@ -299,7 +323,7 @@ class Bicycle {
String name; // default: Only accessible from within this package
// Constructors are a way of creating classes
- // This is a default constructor
+ // This is a constructor
public Bicycle() {
gear = 1;
cadence = 50;
@@ -307,7 +331,7 @@ class Bicycle {
name = "Bontrager";
}
- // This is a specified constructor (it contains arguments)
+ // This is a constructor that takes arguments
public Bicycle(int startCadence, int startSpeed, int startGear, String name) {
this.gear = startGear;
this.cadence = startCadence;