Automatically remove explicit package declarations with import statements in Java

Question

I have a project created by others that includes thousands of class files and has the package names explicitly typed out for every reference to any of their classes. It look

Answer 1

I had the same problem with axis generated files, and I wrote a small groovy script to do this. I doesn't do everything (you have to use organize imports in eclipse after you run it), and I haven't tested it very well, so use it carefully. It's also limited to lowercase package names and camel-cased class names, but it may be a good starting point

def replaceExplicitPackageNamesInFile(File javaFile){
 eol = org.codehaus.groovy.tools.Utilities.eol()

 newFile = ""
 explicitImportExpr = /([^\w])(([a-z0-9]+\.)+)([A-Z][a-zA-Z0-9]+)/
 imports = ""
 javaFile.eachLine { 
  line = it.replaceAll(explicitImportExpr, {
   Object [] match ->
   imports += "import ${match[2]+match[-1]};${eol}"
   match[1]+match[-1]
  })
  newFile += line+"${eol}" 
 }
 newFile2 = ""
 newFile.eachLine { line ->
  newFile2 +=
   line.replaceAll(/(^\s*package.*$)/, {
    Object [] match ->
    match[0] + eol + imports
   } ) + eol
 }
 javaFile.setText(newFile2)
}

def replaceExplicitPackageNamesInDir(File dir){
 dir.eachFileRecurse {
  if (it.isFile() && it.name ==~ /.*\.java\z/){
   println "Processing ${it.absolutePath - dir.absolutePath}"
   replaceExplicitPackageNamesInFile(it)
  }
 }
}

Answer 2

You probably need to replace all javax.swing.. Then do organize imports.

Answer 3

I have been able to remove all explicit package names in interfaces by running the sed command below on target files, then by reorganize imports in eclipse:

sed -e 's/java\.[^ ]*\.//g;s/com\.[^ ]*\.//g'

Answer 4

This thread says:

select the package explorer view, right click on your project, choose source then organise imports. Bobs your uncle - all unwanted imports are removed

To make it better formatted:

Right click project > Source > Organize imports

Now, what remains, is to find a way to strip the fully-qualified names from the code. You may think of some regular expression. Take a look at this library - it seems helpful. This article should also be useful.

Answer 5

I use an Eclipse plugin by Michael Ernst that does what you want. It converts references such as java.util.Collection to Collection with the addition of an import java.util.Collection; at the top of the file.

It is effectively the same thing as using "Source -> Add Import" for a fully-qualified reference except that it lets you do it for an entire .java file at once.

Even better, it lets you batch-process all the .java files you have selected in the Package Explorer. Simply right-click on the selection and select "Source -> Clean qualified Type Declarations" form the contextual menu.

Eclipse update site: http://cqtp.sourceforge.net/eclipse/

Answer 6

IntelliJ Idea has tools to do this on a per-file basis. You can probably also do it in bulk, but I don't know how.

Try out a 30 day evaluation and you'll probably be pleased by more than the import cleanup features.