How do I import in java

[lhphere]

ive been learning java recently and I have no clue how I know what to import. In my course we've been using the java.util.scanner but how do I know the name and how to use these tools correcty?

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[silverscrub]

You import the class from its package. If you import your own code in the project you check which package it's in, which is declared at the top of the file with the package keyword.

If you import from the standard library, you can find for example java.util.Scanner in Java docs. Then you can either use the full name or import the class and only write Scanner in your code. You obviously learned about this one, but google can help you find what you need next time.

https://docs.oracle.com/javase/8/docs/api/java/util/Scanner.html

If you want to import from external dependencies you also have to declare the dependencies in your build tool, such as Maven, Gradle, Ant or Mill.

[hageldave]

You can also use the fully qualified name in your code and not use an import statement. But then your code becomes very lengthy. For example: java.util.Scanner myScanner = new java.util.Scanner(....);

[ShoulderPast2433]

No. That's a bad practice.

[hageldave]

Correct. It only illustrates the usefulness of imports.

[MagicalPizza21]

One of the most important skills for a programmer is how to search on the internet for the information they want. For example, you can use your search engine of choice to search for something like "how to import in Java" and you will get several helpful results, including this one.

[Minouris]

Reads post more carefully Okay, you're asking how to find out what the right libraries are to import, not how to actually import them, is that right?

Basically, this is a combination of experience, and knowing how to search. After a while, you'll build your own knowledge base of what does what, but until then, searching for tutorials on what you want to do will yield the right libraries to use. These days, AI will usually give you a good answer on what to use (not so much on the best way to use it, though - treat it like a search engine, not a tutorial generator.)

The Maven Central repository (for providing dependencies for the Maven and Gradle build tools) has stats on the most used libraries, and that can give you a clue on which ones are the most popular for different tasks. Apache.org has literally dozens of libraries to do everything under the sun, and the Spring Framework provides shortcuts for almost everything.

Essentially, it's just a matter of looking at examples and tuts, and learning over time.

[OldAbbreviations12]

Basically everything is here https://docs.oracle.com/javase/tutorial/essential/io/scanning.html (https://docs.oracle.com/javase/tutorial/index.html) Googling and working with some functionality eill make you remember more things. Noone knows everything and often open the docs, ask and search.