synchronize lazy unpacking in bcel classfile attributes - #364
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Signed-off-by: sayed nabhan <nabhan@bugqore.com>
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LineNumberTable, BootstrapMethods and MethodParameters unpack their raw attribute bytes lazily on the first getter call, but unlike the already-fixed sibling LocalVariableTable they leave unpack()/ensureInflated() and the matching setter/dump unsynchronized. When the same attribute instance parsed from a class is read from more than one weaver thread, one thread can null the shared data array and swap the table reference while another is still inside unpack(), so a caller sees a NullPointerException or a half-populated table back from getTableLength()/getLineNumberTable(). This mirrors the LocalVariableTable fix by synchronizing the lazy-init and its mutators so the fields are published safely, and adds a LineNumberTableConcurrencyTest alongside the existing LocalVariableTableConcurrencyTest that hits the race (NPE before the change) and passes after.