about BufferedReader.readline()

最新推荐文章于 2021-03-15 10:48:21 发布
最新推荐文章于 2021-03-15 10:48:21 发布
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本文链接：https://blog.youkuaiyun.com/qiuleng2002/article/details/6408727
本文通过一个具体的编程案例，讲述了在使用Java进行HTTP请求处理时遇到的一个常见问题：在调试过程中监视表达式导致的数据流提前被消费，进而使得程序逻辑无法按预期执行。作者分享了解决这一问题的经验教训，并提醒开发者在调试涉及流读取的程序时要格外小心。

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BufferedReader reader =

request.getReader();

 

 

while ( (line = reader.readLine()) != null) {

          jsonStrBuf.append(line);

}

 

昨天在调试该程序的时候， reader.readLine()设置为监视表达式，而输入流只有一行，在程序中，无论怎么样循环都进不去，郁闷啊郁闷。最终解决了这个问题，表达式已经事先读取了流，程序中就不会再读取到，低级的错误！！！

 

以后调试程序，表达式在流的读取时，会影响到程序的顺序执行的。请万分注意！！

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} } else { //直接发送 if (message.callbackId) { var callbackResponseId = message.callbackId; responseCallback = function(responseData) { _doSend('response', responseData, callbackResponseId); }; } var handler = WebViewJavascriptBridge._messageHandler; if (message.handlerName) { handler = messageHandlers[message.handlerName]; } //查找指定handler try { handler(message.data, responseCallback); } catch (exception) { if (typeof console != 'undefined') { console.log("WebViewJavascriptBridge: WARNING: javascript handler threw.", message, exception); } } } }); } //提供给native调用,receiveMessageQueue 在会在页面加载完后赋值为null,所以 function _handleMessageFromNative(messageJSON) { if (receiveMessageQueue) { receiveMessageQueue.push(messageJSON); } _dispatchMessageFromNative(messageJSON); } WebViewJavascriptBridge.init = init; WebViewJavascriptBridge.doSend = send; WebViewJavascriptBridge.registerHandler = registerHandler; WebViewJavascriptBridge.removeHandler = removeHandler; WebViewJavascriptBridge.callHandler = callHandler; WebViewJavascriptBridge.callHandlerPersistent = callHandlerPersistent; WebViewJavascriptBridge.registerPersistentCallback = registerPersistentCallback; WebViewJavascriptBridge.removePersistentCallback = removePersistentCallback; WebViewJavascriptBridge._handleMessageFromNative = _handleMessageFromNative; WebViewJavascriptBridge._fetchQueue = _fetchQueue; var readyEvent = document.createEvent('Events'); var jobs = window.WVJBCallbacks || []; readyEvent.initEvent('WebViewJavascriptBridgeReady'); readyEvent.bridge = WebViewJavascriptBridge; window.WVJBCallbacks = []; jobs.forEach(function (job) { job(WebViewJavascriptBridge) }); document.dispatchEvent(readyEvent); })(); public static void webViewLoadLocalJs(WebView view, String path){ String jsContent = assetFile2Str(view.getContext(), path); view.loadUrl("javascript:" + jsContent); } public static String assetFile2Str(Context c, String urlStr){ InputStream in = null; try{ in = c.getAssets().open(urlStr); BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(in)); String line = null; StringBuilder sb = new StringBuilder(); do { line = bufferedReader.readLine(); if (line != null && !line.matches("^\\s*\\/\\/.*")) { sb.append(line); } } while (line != null); bufferedReader.close(); in.close(); return sb.toString(); } catch (Exception e) { e.printStackTrace(); } finally { if(in != null) { try { in.close(); } catch (IOException e) { } } } return null; }注入.js文件报 Uncaught ReferenceError: WebViewJavascriptBridge is not defined -- From line 1 of 发现错误: Uncaught ReferenceError: WebViewJavascriptBridge is not defined https://pv-mall.wuyang-honda.com/h5/#/ 1 6553 ReferenceError: WebViewJavascriptBridge is not defined -- From line 79 of https://pv-mall.wuyang-honda.com/h5/assets/index-EaCfmwlF.js Uncaught ReferenceError: WebViewJavascriptBridge is not defined -- From line 1 of https://pv-mall.wuyang-honda.com/h5/#/ [system] Location: https://pv-mall.wuyang-honda.com/h5/#/ -- From line 10 of https://pv-mall.wuyang-honda.com/h5/assets/vconsole.min-QVp8m_0m.js [system] Client: Android 12 -- From line 10 of https://pv-mall.wuyang-honda.com/h5/assets/vconsole.min-QVp8m_0m.js [system] UA: Mozilla/5.0 (Linux; Android 12; ALN-AL00 Build/HUAWEIALN-AL00; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/114.0.5735.196 Mobile Safari/537.36 Honda_ANDROIDAPP -- From line 10 of https://pv-mall.wuyang-honda.com/h5/assets/vconsole.min-QVp8m_0m.js
最新发布
07-04
如果当前页面还没有加载（比如是新的页面），那么执行JS可能会失败，因为当前页面可能是一个about:blank。 因此，通常的做法是： - 在WebViewClient的onPageStarted中，当页面开始加载时，注入一次桥接代码（注意...
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