Arrays, Loops, & Imports

Loops

Types of Loops in Java

• for : (as in JS): iterates based on set (int) variable that is adjusted through each loop.
  • Example using all three (individually optional) elements: for (int i = 0; i < 10; i++)

  • Can be broken with break (named loop may be specified)

  • Can be named using the following syntax, where “nameHere” is the desired name: nameHere: for (

  • Can iterate over a collection/array. Example iterating over “elementHere” in “arrayHere” for(Type elementHere : arrayHere)

• for each: compact form of iteration, like exampleArr.forEach(exampleElement -> System.out.println(exampleElement));

• while : Defines a condition, then repeats code block until condition is not true or loop is explicitly broken (break). Uses syntax while (conditionHere) {codeBlockHere}

• do-while : Subset of “while” loop that iterates once before checking condition. Syntax: do { codeToDo; } while (condition);

Importing packages

• Recall: Package names in Java are the directory name

• When declared, package must be declared first, followed by imports

• packages may end in wildcard * to include all classes of that package instead of particular classes
  • classes may be fully named (by directory/package) within code instead of imported
• Importing all classes is not significant to performance, and is less error-prone due to potential naming issues caused by explicit class imports