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Logical operators can join many comparisons into one condition.

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In the last lesson, you set up a series of if elsea final statements, notice that each condition only

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has one comparison.

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In this lesson, you're going to connect many comparisons into one condition.

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The first thing I'll need you to do is create a new class by yourself inside the Section three project,

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create a new file named Logical Operators Java, and make sure the class has a main method.

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With a logical operator, we can compare many things at once.

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And the most common logical operators are or and end.

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We're going to start with the owner operator and this one returns true if either comparison is true.

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And there are three parts to the owner operator.

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There's the first comparison, and then there's the owner operator represented by two vertical lines

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such that if any of the comparisons are true, the entire condition becomes true.

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And then there's the second comparison.

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So what are some use cases for the or operator?

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Well, think about this, you're applying for a scholarship and to get the scholarship you need above

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a seventy five in chemistry or in English.

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So we're going to make two integer variables.

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Chemistry grade set that equal to seventy eight.

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An English grade return is set equal to sixty five.

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Now we're going to make if statement where they condition and inside the condition, we're going to

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check if chemistry great is greater than 75, did they get above a 75 in chemistry or we'll check if

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English grade is bigger than 75.

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And if either one of these comparisons is true, the entire condition is going to be true, in which

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case we're going to print.

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Congratulations.

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You got the scholarship.

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Otherwise, we're going to print.

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You didn't get the scholarship.

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All right, I think we're ready to run our coat.

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And the condition is true, you did get the scholarship.

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The or operator checks, if one of the comparisons is true, only one of them has to be true, and the

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first comparison is to the entire condition is true and the code runs.

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Now we're going to change the students chemistry grade to 67.

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We're going to rerun the code.

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And this time the code inside Elsa runs.

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None of the comparisons are true, so the condition is false, so Jarvis skips over and runs the code

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inside ELT's.

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You can combine more than two comparisons.

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You can combine three comparisons into one condition for comparisons, five comparisons, as many as

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you want, as long as one of them is true, the entire condition is going to be true.

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And so back in coat, let's say the school decided to be generous.

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They're also going to offer you a scholarship if you know Java.

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So we're going to make a string variable and set it equal to Java.

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And now we're going to add another comparison to the condition, it's going to check if the variable

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equals Java, does the student know the Java programming language?

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Rewriting our code.

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And we got our scholarship back.

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The or operator checks if one of the comparisons is true.

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First one is false.

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The second one is false, but the last one is true to the entire condition is true and the code inside

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runs.

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Now we're going to talk about the end operator.

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And there are three parts to it as well.

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There is the first comparison, there's the end operator, which is a pair of ampersands and the second

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comparison.

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And with the end operation, the condition is only true if every comparison is true.

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In this case, the first comparison is false.

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So the entire condition becomes false.

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So what are some use cases for the end operator?

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Well, think about this.

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To get your diploma, you need at least 40 credits and a minimum GPA of 2.0.

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Now, credits are whole numbers.

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So we're going to make it into variable credits and we're going to set that equal to fifty six.

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And GPA is a decimal measure.

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So we're going to make a double variable GPA and set it equal to three point two.

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Now we're going to make another statement.

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First, we're going to check if a student has at least 40 credits, credits greater than or equal to

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40 and will check if they have a GPA of at least two point zero.

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And if the student satisfies both requirements, if both of these comparisons are true, we're going

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to print you earned your diploma.

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We're sorry, you need at least 40 credits and a minimum GPA of 2.0.

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All right, we're ready to run our code.

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The condition is indeed true, they got their diploma, the end operator checks, if every comparison

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is true, the student has about 40 credits and has a high enough GPA.

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So the entire condition is true and the coda runs.

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What if we change the students GPA to one point for.

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Rewriting our code.

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This time, they don't get their diploma.

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The end operator needs both comparisons to be true.

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The student has more than 40 credits, but there is too low, so the condition is false in the code

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runs.

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In this lesson, you connected many comparisons to one condition.

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The owner operator returns true if either comparison is true now, a student had a seven eight in chemistry

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and a sixty five in English, and you made a condition that checks if chemistry grade is greater than

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75 or in English, and the first comparison is true.

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And whether or not the second one is false or true, it doesn't matter.

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The entire condition becomes true and the code inside runs.

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Now, the end operator is different, it only returns true if every comparison, if every expression

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is true.

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Now, a student had 56 credits, but a GPA of one point four and you made a condition that checks if

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a student scored above 40 credits and had a minimum GPA of 2.0.

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The end operator needs both comparisons to be true, but one of them is false.

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This means that the entire condition is false and Java skips over to the L statements.