remove thread utils #110

webmagic-core/src/main/java/us/codecraft/webmagic/utils/ThreadUtils.java

-package us.codecraft.webmagic.utils;
-
-import com.google.common.util.concurrent.MoreExecutors;
-
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.SynchronousQueue;
-import java.util.concurrent.ThreadPoolExecutor;
-import java.util.concurrent.TimeUnit;
-
-/**
- * @author code4crafer@gmail.com
- * @since 0.1.0
- */
-public class ThreadUtils {
-
-    /**
-     * @Deprecated
-     * @param threadSize
-     * @return
-     * @see us.codecraft.webmagic.selector.thread.CountableThreadPool
-     */
-    public static ExecutorService newFixedThreadPool(int threadSize) {
-        if (threadSize <= 0) {
-            throw new IllegalArgumentException("ThreadSize must be greater than 0!");
-        }
-        if (threadSize == 1) {
-            return MoreExecutors.sameThreadExecutor();
-        }
-        return new ThreadPoolExecutor(threadSize - 1, threadSize - 1, 0L, TimeUnit.MILLISECONDS,
-                new SynchronousQueue<Runnable>(), new ThreadPoolExecutor.CallerRunsPolicy());
-    }
-}