Bug 355390

Description jwnimmer 2011-08-22 10:01:10 EDT

Build Identifier: I20110613-1736

When a package-info file contains import statements and the organize
imports is set to run as a save action, saving some other file in that
package sometimes inserts the package-info's import statement(s) in
random locations, thus corrupting the saved source code.  This does
not happen consistently, so indicates a race condition.

Workarounds:
 (1) Use fully-qualified names in package-info.java (no imports).
 (2) Disable "organize imports" as a save action.


Reproducible: Sometimes

Steps to Reproduce:
Given a Java project with the following files, turn on organize
imports as a save action (Project -> Properties -> Java Editor -> Save
Actions -> Enable project specific settings -> Perform the selected
actions on save -> Organize imports).

=== annot/Nullable.java ================================================
package annot;

import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;

@Documented
@Retention(RetentionPolicy.RUNTIME)
public @interface Nullable {
}

=== sample/package-info.java ===========================================
@Nullable
package sample;
import annot.Nullable;

=== sample/Thing.java ==================================================
/*
 * This is a large copyright statement.
 * This is a large copyright statement.
 * This is a large copyright statement.
 * This is a large copyright statement.
 * This is a large copyright statement.
 * This is a large copyright statement.
 */
package sample;

public class Thing {
	public class Other {
	}
}

========================================================================

Now when saving Thing.java, the copyright statement is sometimes
corrupted to look like this:

    /*
     * This is a large copyimport annot.Nullable;
    is is a large copyright statement.
     * This is a large copyright statement.
     * This is a large copyright statement.
     * This is a large copyright statement.
     * This is a large copyright statement.
     */
    package sample;

That is, the import statement from package-info.java overwrites some
of the first characters in the file for all files in that package.

This does not occur on every save, suggesting a race condition.  For
me, it happens very reliably when I make an edit and then hit Ctrl-S
immediately afterward (within half a second).

When there is no large copyright statement, it's even worse -- actual
program code is overwritten, or for very short files (like Thing.java
with comments removed) I get an ArrayIndexOutOfBounds exception during
save (error info to be attached to the bug report in a moment).