fix a httpclient pool size bug

webmagic-core/src/main/java/us/codecraft/webmagic/Spider.java

@@ -39,7 +39,7 @@ import java.util.concurrent.atomic.AtomicInteger;
  */
 public class Spider implements Runnable, Task {
 
-    private Downloader downloader = new HttpClientDownloader();
+    private Downloader downloader;
 
     private List<Pipeline> pipelines = new ArrayList<Pipeline>();
 
@@ -139,12 +139,18 @@ public class Spider implements Runnable, Task {
         return this;
     }
 
+    protected void checkComponent() {
+        if (downloader == null) {
+            this.downloader = new HttpClientDownloader();
+        }
+    }
 
     @Override
     public void run() {
         if (!stat.compareAndSet(STAT_INIT, STAT_RUNNING)) {
             throw new IllegalStateException("Spider is already running!");
         }
+        checkComponent();
         if (startUrls != null) {
             for (String startUrl : startUrls) {
                 scheduler.push(new Request(startUrl), this);
@@ -247,6 +253,7 @@ public class Spider implements Runnable, Task {
         if (threadNum <= 0) {
             throw new IllegalArgumentException("threadNum should be more than one!");
         }
+        downloader = new HttpClientDownloader(threadNum);
         if (threadNum == 1) {
             return this;
         }

webmagic-core/src/main/java/us/codecraft/webmagic/downloader/HttpClientDownloader.java

@@ -21,6 +21,7 @@ import java.io.IOException;
 
 /**
  * 封装了HttpClient的下载器。已实现指定次数重试、处理gzip、自定义UA/cookie等功能。<br>
+ *
  * @author code4crafter@gmail.com <br>
  *         Date: 13-4-21
  *         Time: 下午12:15
@@ -29,11 +30,21 @@ public class HttpClientDownloader implements Downloader {
 
     private Logger logger = Logger.getLogger(getClass());
 
+    private int poolSize;
+
+    public HttpClientDownloader(int poolSize) {
+        this.poolSize = poolSize;
+    }
+
+    public HttpClientDownloader() {
+        this(5);
+    }
+
     @Override
     public Page download(Request request, Task task) {
         Site site = task.getSite();
         logger.info("downloading page " + request.getUrl());
-        HttpClient httpClient = HttpClientPool.getInstance().getClient(site);
+        HttpClient httpClient = HttpClientPool.getInstance(poolSize).getClient(site);
         String charset = site.getCharset();
         try {
             HttpGet httpGet = new HttpGet(request.getUrl());
@@ -50,7 +61,7 @@ public class HttpClientDownloader implements Downloader {
                         logger.warn("download page " + request.getUrl() + " error", e);
                         return null;
                     }
-                    logger.info("download page " + request.getUrl() + " error, retry the "+tried+" time!");
+                    logger.info("download page " + request.getUrl() + " error, retry the " + tried + " time!");
                     retry = true;
                 }
             } while (retry);

webmagic-core/src/main/java/us/codecraft/webmagic/downloader/HttpClientPool.java

@@ -24,9 +24,16 @@ import java.util.Map;
  */
 public class HttpClientPool {
 
-    public static final HttpClientPool INSTANCE = new HttpClientPool(5);
+    public static volatile HttpClientPool INSTANCE;
 
-    public static HttpClientPool getInstance() {
+    public static HttpClientPool getInstance(int poolSize) {
+        if (INSTANCE == null) {
+            synchronized (HttpClientPool.class) {
+                if (INSTANCE == null) {
+                    INSTANCE = new HttpClientPool(poolSize);
+                }
+            }
+        }
         return INSTANCE;
     }
 
@@ -48,7 +55,7 @@ public class HttpClientPool {
 
         HttpProtocolParamBean paramsBean = new HttpProtocolParamBean(params);
         paramsBean.setVersion(HttpVersion.HTTP_1_1);
-        paramsBean.setContentCharset("UTF-8");
+        paramsBean.setContentCharset(site.getCharset());
         paramsBean.setUseExpectContinue(false);
 
         SchemeRegistry schemeRegistry = new SchemeRegistry();

webmagic-samples/src/main/java/us/codecraft/webmagic/samples/GlobalProcessor.java

@@ -27,8 +27,8 @@ public class GlobalProcessor implements PageProcessor {
 
     @Override
     public Site getSite() {
-        if (site==null){
-            site = Site.me().setDomain("www.2345.com")
+        if (site == null) {
+            site = Site.me().setDomain("www.2345.com").setSleepTime(0)
                     .addStartUrl("http://www.2345.com/").addStartUrl("http://hao.360.cn/")
                     .addStartUrl("http://www.baidu.com/s?wd=%E7%BD%91%E7%AB%99%E5%AF%BC%E8%88%AA&rsv_spt=1&issp=1&rsv_bp=0&ie=utf-8&tn=80039098_oem_dg&rsv_n=2&rsv_sug3=6&rsv_sug4=698&rsv_sug=0&rsv_sug1=3")
                     .setUserAgent("Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_2) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.65 Safari/537.31");