question: public void add ( JarEntry entry , byte [ ] bytes , boolean overwrite ) throws IOException { JarEntry newEntry = new JarEntry ( entry . getName ( ) ) ; newEntry . setSize ( bytes . length ) ; if ( jarEntries . containsKey ( entry . getName ( ) ) && ! overwrite ) { throw new IOException ( "Archive already contains entry: " + entry ) ; } else { jarEntries . remove ( entry . getName ( ) ) ; jarEntriesToAdd . remove ( entry . getName ( ) ) ; jarEntries . put ( entry . getName ( ) , newEntry ) ; jarEntriesToAdd . put ( entry . getName ( ) , bytes ) ; } }
target:  Adds (or optionally overwrites) an archive entry with the specified entry properties.  