Lock Obtain timed out:lock@ solution (Lucene)

Java.io.IOException:Lock Obtain timed Out:lock@f:/tomcat 5.0/temp/ Lucene-424c6f3ac55284d5cd628ea4fb464f10-write.lock
At Org.apache.lucene.store.Lock.obtain (lock.java:56)
At Org.apache.lucene.index.indexwriter.<init> (indexwriter.java:254)
At Org.apache.lucene.index.indexwriter.<init> (indexwriter.java:204)

There are two main reasons for these anomalies:
1. The application shuts down until the system is writing an index that is not completed
Workaround: Restart the app after deleting the prompt lock file (preferably captured in the app, automatically deleted)
2. There are multiple threads or programs in the system in the grab index
Workaround: Add or improve the wait queue mechanism, or unlock it when this error occurs

Indexreader.unlock (Directory dir);