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primitives, declare instantiate intialize, common imports
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@@ -252,4 +252,59 @@ In fact, it's likely that aspiring Software Engineers will want to get used to t
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{
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// print the file
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}
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}
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}
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### Most Common Imports
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```java
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import static java.lang.System.out;
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> out.println("shorthand println");
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import java.io.File; // Read and Write files
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> File input = new File("input1.dat"); // can be thrown directly into a Scanner's input
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import java.io.FileNotFoundException;
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> public static void main(String[] args ) throws FileNotFoundException {
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import java.util.Scanner;
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> Scanner s = new Scanner();
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> s.nextInt();
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> s.hasNextInt();
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> s.nextLine();
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import java.util.Arrays;
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> Arrays.toString(new int[]{});
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```
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### Declare, Instantiate, Initalize
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* Declaration: The code set in bold are all variable declarations that associate a variable name with an object type.
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```java
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type name;
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int age;
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double magnitude;
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Point origin;
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```
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* Instantiation: The new keyword is a Java operator that creates the object.
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```java
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Point origin = new Point();
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```
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* Initialization: The new operator is followed by a call to a constructor, which initializes the new object. Instantiation and Initalization almost always occur on the same line, in the same instant.
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```java
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class Point
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{
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private int x;
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private int y;
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Point(int x, int y) <--- Initalization
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{ <--- is
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this.x = x; <--- occurring
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this.y = y; <--- right
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} <--- here
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}
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```
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### When Primitive Array Casts Are Required
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Primitive Arrays can be declared and
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```java
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int[] myIntArray = new int[3];
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int[] myIntArray = {1, 2, 3};
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int[] myIntArray = new int[]{1, 2, 3};
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```
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