Java Chapter 5 (Extra-Strength Methods)

Important Concepts:

Operators:

• "x = 4" Sets the value of x to 4.
• "if (x == 4)" Checks to see if value of x is 4 (returns True/False).
• "<; >; <=, >=" Compares x to something else. Less than etc.

Loops:

• while (x > 4) This will continuously loops until the condition becomes untrue.

For loops:

• for(int x = 10; x < 20; x += 1) Here, x will increase by 1 until x >= 20.

Random numbers:

• import java.util.Random;
• then later add:
• int randomInt = randomGenerator.nextInt(100)
• which will create a random number 0-99.

String > Int:

• int x = Integer.parseInt("1234");

Int > String:

• int integer = 42; String string = integer + "";

BattleShip Project:

Here's some proof that I completed the BattleShip projects. The first screenshot is the different files needed to compile, and the second screenshot is proof that it executes.

One issue with this is that if you simply typed "3" three times, you'd technically get 3 hits, and you'd win. So as long as you find one hit, you can win. You'd solve this by adding code that would prevent you from typing the same number twice.

Java Chapter 4

This chapter focused on several topics, including parameters, arguments, and operators.

The '=' sign is important in Java, and x = y is used when you're changing the value of x to the value of y. You'd use x == y when you're comparing the value of the two variables (must be primitive variables). For instance, you'd use:

if (x == y) {
   x += 1;
}

If you want to see if two things are UNequal, you'd use != such as in:

if (x != y) {
   x -= 1;
}

Any interesting thing, however, is when you try to compare Strings. you must use .equals(). For example:

String var = "Jose";
if ("Jose".equals(var)) {
   var = "Joes";
}

Here's a personal example of how .equals() is used, as well as "==":

If you don't know what's going on here, I'm comparing a string in a list (names) to the variable "search."

The following are some of the important ideas from this chapter:

• Methods can have parameters, such as setTeamScore(team, score) has the team and score parameters. You could say setTeamScore(home, 45).
• Methods can accept literal values like "3" or 3, but can also take variables like glove or baseball, if glove = "glove" and baseball = 3, for example.
• If a method is declared as boolean, it must return a boolean answer. You'd call it "void" if it didn't need a response.

So, I created a little "comparison" between Python and Java for using iterations. Both programs find the the words in a list containing the letter "a". Here ya go:

Java:

Python:

As you'll notice, Python is so much simpler and easier to understand.