06 - Strings in Java/003 Escape Sequences in Java_en.srt

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Hello team!

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In this lesson we will learn with you escape sequences in Java.

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Let me show you what is escape sequence and how to escape characters.

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I believe you already understood that all string literals need to be enclosed in quotation marks.

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But what to do in case you need to have string which will contain quotes in itself?

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In this example I want to put book name in quotes.

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To do this, I need to use character escaping by using a special symbol backslash.

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I can escape quotation marks.

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In Java, a backslash combined with a character to be escaped is called an escape sequence.

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In case I don't use backslash in this example, there will be compilation error.

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Java compiler is very smart program, but it will be hard for it to compile string in such format.

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Java compiler expects that each string is started with quote and ended with quote.

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That's why without escape sequence for Java compiler, it will be impossible to understand that you

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want to have this string as part of the whole string.

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Let's consider another example.

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You want to have string which will contain directory path on your computer and you need to use backslash.

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But Java compiler knows that in source code will use backslash only in case we want to create escape

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sequence, and in this case compiler simply cannot find escape sequence because you don't need to escape

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J character.

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That's why you need to escape your backslash character.

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And we have here double backslash in the source code but single backslash in the output.

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In Java there are limited amount of escape sequences.

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Here you can find all lists of escape sequences for example backslash and t inserts, tab character

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backslash and n inserts newline character.

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Here is an example with two lines in one string object.

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You see backslash and n here.

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And here is the output.

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Here is one line and the second line.

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I encourage you to try these escape sequences in your source code.

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Another important thing to know about escaping characters in Java Unicode table includes the symbols

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of almost every written language in the world.

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In case you need to use Unicode character in your string, you can just escape Unicode code.

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All Unicode characters codes have the form U plus hexadecimal number.

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So if you need to use character from Unicode table, just escape this value and you will see copyright

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character in the output.

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That's all.

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Thank you for your attention and see you in the next lesson.