You may have this already but in case not…
I have just turned on the Eclipse option to warn when variable declarations shadow another of the same name:
Preferences | Java | Compiler | Errors/Warnings
…after noticing a case of this by manual inspection (never easy without help from the IDE).
Of course what to do if the warning is raised needs some thought…
if it is really a different variable, change the name to avoid confusion
if it should be the shadowed variable, change the declaration (having worked out the impact)
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