有一個(gè)大List集合，遍歷進(jìn)行一些耗時(shí)操作，不能達(dá)到性能要求，查詢?nèi)罩荆瑔蝹€(gè)任務(wù)雖然有不少數(shù)據(jù)庫和第三方API請(qǐng)求，比較耗時(shí)，但返回效率尚可，所以優(yōu)先采用多線程方式進(jìn)行處理并行請(qǐng)求數(shù)據(jù)庫和第三方API，因?yàn)樘幚硗赀€要對(duì)list所屬的數(shù)據(jù)進(jìn)行操作，所以，線程池多線程處理要等待全部處理完。

相關(guān)的代碼如下：

@Test
public?void?testTB()
{
??List??list?=?new?ArrayList??();
??for(int?i?=?0;?i?900;?i++)
??{
????list.add("a");
??}
??ExecutorService?touchWorker?=?Executors.newFixedThreadPool(4,?new?ThreadFactoryBuilder().setNameFormat("touch-send-worker-%d").build());
??int?size?=?list.size();
??if(size?>?100)
??{
????int?batch?=?size?%?100?==?0???size?/?100?:?size?/?100?+?1;
????for(int?j?=?0;?j?????{
??????int?end?=?(j?+?1)?*?100;
??????if(end?>?size)
??????{
????????end?=?size;
??????}
??????List??subList?=?list.subList(j?*?100,?end);
??????touchWorker.execute(()?-?>?sleepTest(subList));
????}
????touchWorker.shutdown();
????while(true)
????{
??????if(touchWorker.isTerminated())
??????{
????????break;
??????}
????}
??}
??else
??{
????sleepTest(list);
??}
}
private?void?sleepTest(List??subList)
{
??for(String?i:?subList)
??{
????try
????{
??????//耗時(shí)操作
??????System.out.println("######"?+?i?+?"######"?+?Thread.currentThread().getName());
??????//????????????????Thread.sleep(1000*30);
????}
????catch(Exception?e)
????{
??????e.printStackTrace();
????}
??}
}

void shutdown()

啟動(dòng)一次順序關(guān)閉，執(zhí)行以前提交的任務(wù)，但不接受新任務(wù)。若已經(jīng)關(guān)閉，則調(diào)用沒有其他作用。

拋出：SecurityException - 如果安全管理器存在并且關(guān)閉，此 ExecutorService 可能操作某些不允許調(diào)用者修改的線程（因?yàn)樗鼪]有保持RuntimePermission("modifyThread")），或者安全管理器的 checkAccess 方法拒絕訪問。

boolean isTerminated()

若關(guān)閉后所有任務(wù)都已完成，則返回true。注意除非首先調(diào)用shutdown或shutdownNow，否則isTerminated永不為true。返回：若關(guān)閉后所有任務(wù)都已完成，則返回true。

當(dāng)然還有一種方法，是之前寫的，方法比上邊的臃腫了，不過會(huì)獲取返回結(jié)果進(jìn)行處理：邏輯是獲取所有頁面的List，多線程遍歷List后，將所有頁面的違規(guī)詞查出發(fā)送郵件，代碼：

/**
?*??落地頁違規(guī)詞排查(多線程)。
?*?@return
?*/
@Test
public??void?getViolationsLandpageByThreadPool()?{
????try?{
????????landPageService.getViolationsLandpageByThreadPool("1年");
????}?catch?(Exception?e)?{
????????e.printStackTrace();
????}
}

//?開始時(shí)間
long?start?=?System.currentTimeMillis();
/*List?list?=?new?ArrayList();
for?(int?i?=?1;?i?<=?3000;?i++)?{
????list.add(i?+?"");
}*/

List?list?=?landPageDao.getPageIdAndPath();
//?初始化敏感詞庫對(duì)象
SensitiveWordInit?sensitiveWordInit?=?new?SensitiveWordInit();
//?從數(shù)據(jù)庫中獲取敏感詞對(duì)象集合（目前先放在資源文件中，等以后比較多或者需要界面操作時(shí)再用數(shù)據(jù)庫）
//?構(gòu)建敏感詞庫
Map?sensitiveWordMap?=?sensitiveWordInit.initKeyWord(vioKey);
//?傳入SensitivewordEngine類中的敏感詞庫
SensitivewordEngine.sensitiveWordMap?=?sensitiveWordMap;
//?每500條數(shù)據(jù)開啟一條線程
int?threadSize?=?11000;
//?總數(shù)據(jù)條數(shù)
int?dataSize?=?list.size();
//?線程數(shù)
int?threadNum?=?dataSize?/?threadSize?+?1;
//?定義標(biāo)記,過濾threadNum為整數(shù)
boolean?special?=?dataSize?%?threadSize?==?0;

/*list.parallelStream().forEach(url?->{});*/
//?創(chuàng)建一個(gè)線程池
ExecutorService?exec?=?Executors.newFixedThreadPool(threadNum);
//?定義一個(gè)任務(wù)集合
List>>?tasks?=?new?ArrayList>>();
Callable>?task?=?null;
List?cutList?=?null;

//?確定每條線程的數(shù)據(jù)
for?(int?i?=?0;?i?????if?(i?==?threadNum?-?1)?{
????????if?(special)?{
????????????break;
????????}
????????cutList?=?list.subList(threadSize?*?i,?dataSize);
????}?else?{
????????cutList?=?list.subList(threadSize?*?i,?threadSize?*?(i?+?1));
????}
????// System.out.println("第"?+?(i + 1)?+?"組："?+ cutList.toString());
????final?List?listStr?=?cutList;
????task?=?new?Callable>()?{

????????@Override
????????public?List?call()?throws?Exception?{
//??????????????????? System.out.println(Thread.currentThread().getName()?+?"線程："?+ listStr.get(0).getPageId());
?????????????List?result?=?new?ArrayList();
?????????????for?(LandPage?landPage?:?listStr)?{
?????????????????Long?pageId?=?landPage.getPageId();
?????????????????String?path?=?landPage.getPath();
?????????????????Integer?version?=?landPage.getVersion();
?????????????????String?pageUrl?=?landPage.getPageUrl();
?????????????????String?actualUser?=?landPage.getActualUser();
?????????????????Integer?pageType?=?landPage.getPageType();
?????????????????if?(StringUtils.isNotBlank(path))?{
?????????????????????//?調(diào)用第一個(gè)方法，獲取html字符串
?????????????????????String?html?=?httpRequest(path);
?????????????????????//?調(diào)用第二個(gè)方法，獲取包含的違規(guī)詞
?????????????????????if(StringUtils.isNotBlank(html)){
?????????????????????????html?=?html.replaceAll("","");
//??????String?buffer?=?htmlFiter2(html);
????????????????????????Set?bufferSet?=?SensitivewordEngine.getSensitiveWord(html,?1);//?得到敏感詞有哪些，傳入2表示獲取所有敏感詞//sensitiveWordFiltering(html);
????????????????????????/*String[]?word?=?{"備案","錯(cuò)過將延誤","僅需1980元"};
????????????????????????for(int?i=0?;i????????????????????????????if(html.contains(word[i])){
????????????????????????????????bufferSet.add(word[i]);
????????????????????????????}
????????????????????????}*/
????????????????????????String[]?word?=?{
????????????????????????????"一年","1年學(xué)完","一年學(xué)完","1年內(nèi)學(xué)完","一年內(nèi)學(xué)完"
????????????????????????};
????????????????????????for(int?i=0?;i????????????????????????????if(html.contains(word[i])){
????????????????????????????????bufferSet.add(word[i]);
????????????????????????????}
????????????????????????}
????????????????????????if?(null!=bufferSet&&bufferSet.size()>0)?{

????????????????????????????String?sensitiveWord?=?bufferSet?==?null???null?:?bufferSet.toString();
????????????????????????????if?("[]".equals(sensitiveWord)){
????????????????????????????????sensitiveWord?=?"";
????????????????????????????}
????????????????????????????LandPage?page?=?new?LandPage();
????????????????????????????page.setPageId(pageId);
????????????????????????????page.setPath(path);
????????????????????????????page.setVersion(version);
????????????????????????????page.setDescription(sensitiveWord);
????????????????????????????page.setPageUrl(pageUrl);
????????????????????????????page.setActualUser(actualUser);
????????????????????????????page.setPageType(pageType);
????????????????????????????result.add(page);
????????????????????????????System.out.println(pageUrl);
????????????????????????}
????????????????????}
????????????????}
????????????}
????????????return?(List)?result;
????????}
????};
????//?這里提交的任務(wù)容器列表和返回的Future列表存在順序?qū)?yīng)的關(guān)系
????tasks.add(task);
}

List>>?results?=?exec.invokeAll(tasks);
List?result?=?new?ArrayList();
for?(Future>?future?:?results)?{
????result.addAll(future.get());
}

//?關(guān)閉線程池
exec.shutdown();
System.out.println("線程任務(wù)執(zhí)行結(jié)束");
System.err.println("執(zhí)行任務(wù)消耗了?："?+?(System.currentTimeMillis()?-?start)?+?"毫秒");

System.out.println("共有###########"+list.size()?);

result就是需要發(fā)送郵件的相關(guān)結(jié)果了

END

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