public Builder threadCount(int threadCount) {
      this.threadCount = threadCount;
      return this;
    }
Specifies the number of threads in the pool. Creates fixed thread pool if &gt;. Default is 0
which means (non-fixed) cached thread pool.

@param threadCount the number of threads in the pool
@return a reference to this builder
geode-junit/src/main/java/org/apache/geode/test/junit/rules/ExecutorServiceRule.java