Bug 39720 Adding external jar to the Build Path of an existing Java project [build path]
When adding an external jar file to an existing Java project, the "Setting Build Path" error dialog is displayed. The dialog displays the text "An error occured while setting the build path. Reason: /usr does not exist". The jar to be added in this case is located in the /usr/local/bin/ directory. I am working with the release 2.1 build for linux.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/CPListElement.java
fCachedEntry= null;
	}
	
	
	/*
	 * @see Object#equals(java.lang.Object)
	 */
	public boolean equals(Object other) {
		if (other != null && other.getClass().equals(getClass())) {
			CPListElement elem= (CPListElement)other;
			return elem.fEntryKind == fEntryKind && elem.fPath.equals(fPath);
		}
		return false;
	}
	
	/*
	 * @see Object#hashCode()
	 */
	public int hashCode() {
		return fPath.hashCode() + fEntryKind;
	}
	/**
	 * Returns if a entry is missing.
	 * @return Returns a boolean
	 */
	public boolean isMissing() {
		return fIsMissing;
	}
	/**
	 * Sets the 'missing' state of the entry.