CODEWITHSUNDEEP
java
Ayushya
Ayushya

Reputation: 10407

In JAVA, how do I determine where an import is coming from?

Am not using any IDE and trying to fix some errors for a deployed war file in tomcat. I am trying to look for source of a package and Erroneous line seems to require parameters and has been imported from some package like 

import com.somefirm.somepackage.someClass;

Following questions did not have answer my question:

In eclipse determine which jar file a class is from

How can I find files imported in a java class

I want to know is there any way I can find source of import manually. Is it even possible or not? How does a class look for packages to import?

Edit 1: Separated the links with a newline.

Edit 2: "am not using any IDE at the moment" was a bit late in the question. SO added Am not using IDE to first line.

Edit 3: Provided more clarity to the question, as to why I am needing it.

Edit 4: Added these edits. Thanks to @Jude-niroshan and @ErwinBolwidt

Upvotes: 3

Views: 5094

Answers (1)

GhostCat
GhostCat

Reputation: 140427

The point is: the exact location of a class is determined by your class path setup.

You define at some point which classes are available when compiling your application respectively which classes to ship with it.

So, when you are not using an ide - you have to search the "elements" in the class path that gets applied for your build. For example by looking into each jar file.

Given your comments: I think you have to step back. You seem to lack basic knowledge of Java. You have to understand how that WAR file is built. There should be some sort of build description; containing the dependencies and other contents of the WAR delivery. You have to analyse those. Beyond that: if these packages are from your team/company/... a simple file search might do the job. If those packages are "external", like open source libraries - then you might try to simple google for the class name; or turn to grepcode.com.

And the other thing you asked: a compiled class contains only fully qualified class names. There are no import statements in class files any more. So when a class "needs" another class, it asks the JVM to load that class (given the fully qualified name). And the JVM simply looks into the classpath, and loads the first class that matches the given name.

Upvotes: 4

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