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Merge pull request #411 from adambrenecki/java-errors
[java/en] Fix errors specified in #410.
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ad848fe6ca
@ -26,7 +26,8 @@ import java.util.ArrayList;
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// Import all classes inside of java.security package
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// Import all classes inside of java.security package
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import java.security.*;
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import java.security.*;
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// Each .java file contains one public class, with the same name as the file.
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// Each .java file contains one outer-level public class, with the same name as
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// the file.
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public class LearnJava {
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public class LearnJava {
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// A program must have a main method as an entry point
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// A program must have a main method as an entry point
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@ -84,7 +85,7 @@ public class LearnJava {
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// Char - A single 16-bit Unicode character
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// Char - A single 16-bit Unicode character
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char fooChar = 'A';
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char fooChar = 'A';
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// Use final to make a variable immutable
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// final variables can't be reassigned to another object
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final int HOURS_I_WORK_PER_WEEK = 9001;
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final int HOURS_I_WORK_PER_WEEK = 9001;
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// Strings
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// Strings
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@ -99,7 +100,7 @@ public class LearnJava {
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System.out.println(bazString);
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System.out.println(bazString);
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// Arrays
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// Arrays
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//The array size must be decided upon declaration
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//The array size must be decided upon instantiation
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//The format for declaring an array is follows:
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//The format for declaring an array is follows:
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//<datatype> [] <var name> = new <datatype>[<array size>];
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//<datatype> [] <var name> = new <datatype>[<array size>];
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int [] intArray = new int[10];
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int [] intArray = new int[10];
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@ -161,10 +162,13 @@ public class LearnJava {
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// Incrementations
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// Incrementations
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int i = 0;
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int i = 0;
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System.out.println("\n->Inc/Dec-rementation");
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System.out.println("\n->Inc/Dec-rementation");
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System.out.println(i++); //i = 1. Post-Incrementation
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// The ++ and -- operators increment and decrement by 1 respectively.
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System.out.println(++i); //i = 2. Pre-Incrementation
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// If they are placed before the variable, they increment then return;
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System.out.println(i--); //i = 1. Post-Decrementation
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// after the variable they return then increment.
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System.out.println(--i); //i = 0. Pre-Decrementation
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System.out.println(i++); //i = 1, prints 0 (post-increment)
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System.out.println(++i); //i = 2, prints 2 (pre-increment)
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System.out.println(i--); //i = 1, prints 2 (post-decrement)
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System.out.println(--i); //i = 0, prints 0 (pre-decrement)
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///////////////////////////////////////
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///////////////////////////////////////
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// Control Structures
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// Control Structures
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@ -211,19 +215,19 @@ public class LearnJava {
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//Iterated 10 times, fooFor 0->9
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//Iterated 10 times, fooFor 0->9
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}
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}
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System.out.println("fooFor Value: " + fooFor);
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System.out.println("fooFor Value: " + fooFor);
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// For Each Loop
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// For Each Loop
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// An automatic iteration through an array or list of objects.
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// An automatic iteration through an array or list of objects.
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int[] fooList = {1,2,3,4,5,6,7,8,9};
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int[] fooList = {1,2,3,4,5,6,7,8,9};
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//for each loop structure => for(<object> : <array_object>)
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//for each loop structure => for(<object> : <array_object>)
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//reads as: for each object in the array
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//reads as: for each object in the array
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//note: the object type must match the array.
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//note: the object type must match the array.
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for( int bar : fooList ){
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for( int bar : fooList ){
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//System.out.println(bar);
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//System.out.println(bar);
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//Iterates 9 times and prints 1-9 on new lines
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//Iterates 9 times and prints 1-9 on new lines
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}
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}
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// Switch Case
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// Switch Case
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// A switch works with the byte, short, char, and int data types.
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// A switch works with the byte, short, char, and int data types.
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// It also works with enumerated types (discussed in Enum Types),
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// It also works with enumerated types (discussed in Enum Types),
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@ -246,7 +250,7 @@ public class LearnJava {
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break;
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break;
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}
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}
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System.out.println("Switch Case Result: " + monthString);
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System.out.println("Switch Case Result: " + monthString);
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// Conditional Shorthand
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// Conditional Shorthand
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// You can use the '?' operator for quick assignments or logic forks.
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// You can use the '?' operator for quick assignments or logic forks.
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// Reads as "If (statement) is true, use <first value>, otherwise, use <second value>"
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// Reads as "If (statement) is true, use <first value>, otherwise, use <second value>"
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@ -294,14 +298,14 @@ public class LearnJava {
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trek.speedUp(3); // You should always use setter and getter methods
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trek.speedUp(3); // You should always use setter and getter methods
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trek.setCadence(100);
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trek.setCadence(100);
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// toString is a convention to display the value of this Object.
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// toString returns this Object's string representation.
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System.out.println("trek info: " + trek.toString());
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System.out.println("trek info: " + trek.toString());
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} // End main method
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} // End main method
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} // End LearnJava class
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} // End LearnJava class
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// You can include other, non-public classes in a .java file
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// You can include other, non-public outer-level classes in a .java file
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// Class Declaration Syntax:
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// Class Declaration Syntax:
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@ -319,7 +323,7 @@ class Bicycle {
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String name; // default: Only accessible from within this package
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String name; // default: Only accessible from within this package
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// Constructors are a way of creating classes
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// Constructors are a way of creating classes
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// This is a default constructor
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// This is a constructor
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public Bicycle() {
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public Bicycle() {
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gear = 1;
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gear = 1;
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cadence = 50;
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cadence = 50;
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@ -327,7 +331,7 @@ class Bicycle {
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name = "Bontrager";
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name = "Bontrager";
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}
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}
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// This is a specified constructor (it contains arguments)
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// This is a constructor that takes arguments
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public Bicycle(int startCadence, int startSpeed, int startGear, String name) {
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public Bicycle(int startCadence, int startSpeed, int startGear, String name) {
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this.gear = startGear;
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this.gear = startGear;
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this.cadence = startCadence;
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this.cadence = startCadence;
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