Can anyone please tell me where to download J2SE SDK and corresponding API documentation?

[Steve Yee]

Hello,
     As a total beginner just started to learn Java. I use Head First Java as my 101 textbook.
     In its intro part it tells me to download Java 2 Standard Edition SDK and API Documentation and gives me the links from sun.com, but now it's already been directed to oracle page and I cannot find the exactly corresponding pages.
     I know Java 2 Standard Edition is now Java SE, but is the SDK included in Java SE package? And which version should I pick? the newest version（SE15）?
     And I even don't know where I can get the API Doucmentation... Just because I really have no idea about what it is.
     Those questions sound stupid but anyone tell me about it? Thank you.

[Campbell Ritchie]

Welcome to the Ranch

The book HFJ is now quite old, but they are planning a new edition. Sun no longer exist, so you will have to look elsewhere for your downloads. I haven't downloaded an API file for a long time, but this is where you will find the most recent API. Go here to download the JDK: go for the “ready for use JDK 15” link. Make sure you update your system/user PATH with the path to the new Java® installation at its beginning.
If you use Windows, tell us what you did and I might have to update our FAQ.

[Tim Holloway]

Oracle has kept the http://java.sun.com website alive, and you should still be able to download the SDK from there.

Having said that, The Linux operating system now has OpenJDK and as far as I know, it's no longer a second-rate platform. That's important because: A) it's often part of the standard OS distros and B) Oracle is getting progressively less generous over time as it attempts to make Java a money-maker.

OpenJDK is available on Linux, MacOS, BSD Unix and Windows.

[Steve Yee]

Campbell Ritchie wrote:Welcome to the Ranch

The book HFJ is now quite old, but they are planning a new edition. Sun no longer exist, so you will have to look elsewhere for your downloads. I haven't downloaded an API file for a long time, but this is where you will find the most recent API. Go here to download the JDK: go for the “ready for use JDK 15” link. Make sure you update your system/user PATH with the path to the new Java® installation at its beginning.
If you use Windows, tell us what you did and I might have to update our FAQ.

Thank you very much. I know HFJ is kind of old, in that case, any suggestion on equally reliable and 101-reader-friendly books?

[Campbell Ritchie]

Steve Yee wrote:. . . any suggestion on equally reliable and 101-reader-friendly books?

Wait for the next edition of HFJ. Anybody else?

[Campbell Ritchie]

Steve Yee wrote:. . . Thank you . . .

That's a pleasure Did you get your installation to work?

[Steve Yee]

Campbell Ritchie wrote:

Steve Yee wrote:. . . Thank you . . .

That's a pleasure Did you get your installation to work?

Yep it works, ready for typing some code haha
Though as a beginner I really don't know what API Documentation is for and how to download it(as it is DOCUMENTATION I don't think I have to download it but the book recommends me to do so), I guess I just need to go through the book for now.

[Tim Holloway]

The primary API documentation is JavaDocs. JavaDocs can be automatically produced by running the javadoc utility program against Java source code with specially-formatted comments. IDEs such as Eclipse can even run the javadoc on your own project source code.

The standard output from javadoc is a series of HTML pages suitable for hosting on a webserver. When Oracle releases a new version of Java, they generate JavaDocs and publish them on their own website.

For example: https://docs.oracle.com/javase/7/docs/api/index.html?java/sql/Date.html

The concept is actually older that Java. For example, When I developed for the Commodore Amiga back in the min-1980s, they had a similar system for C code called AutoDoc and their paper manuals were generated from there and then sent to their publisher (Addision-Wesley). I created a system of my own using scripts for C++ in the early 1990s. It output MS-Word Rich Text Format.

Non-Java systems these days often document themselves via a program called Doxygen. It lifts some of its features from JavaDoc.

And, incidentally, while most of the published JavaDocs you see are pretty sparing, you can, at your option add all sorts of secondary information, including HTML tables, graphics, and long rambling treatises. To be re-generated at will if you change the sources.

[Steve Yee]

Tim Holloway wrote:The primary API documentation is JavaDocs. JavaDocs can be automatically produced by running the javadoc utility program against Java source code with specially-formatted comments. IDEs such as Eclipse can even run the javadoc on your own project source code.

The standard output from javadoc is a series of HTML pages suitable for hosting on a webserver. When Oracle releases a new version of Java, they generate JavaDocs and publish them on their own website.

For example: https://docs.oracle.com/javase/7/docs/api/index.html?java/sql/Date.html

The concept is actually older that Java. For example, When I developed for the Commodore Amiga back in the min-1980s, they had a similar system for C code called AutoDoc and their paper manuals were generated from there and then sent to their publisher (Addision-Wesley). I created a system of my own using scripts for C++ in the early 1990s. It output MS-Word Rich Text Format.

Non-Java systems these days often document themselves via a program called Doxygen. It lifts some of its features from JavaDoc.

And, incidentally, while most of the published JavaDocs you see are pretty sparing, you can, at your option add all sorts of secondary information, including HTML tables, graphics, and long rambling treatises. To be re-generated at will if you change the sources.

That's pretty detailed! Thank you.