小编use*_*133的帖子

public void get10FirstLines()
{ 
     StreamReader sr = new StreamReader(path);
     String lines = "";
     lines = sr.readLine();
}

如何在字符串中获取文件的前10行？

当它停止工作时,我收到此错误:

mai 06, 2015 12:47:58 AM org.apache.coyote.http11.AbstractHttp11Processor process
INFO: Error parsing HTTP request header
 Note: further occurrences of HTTP header parsing errors will be logged at DEBUG level.

此后所有其他错误都是一样的.我试图阻止get-requests,但反正一段时间后崩溃了.你有什么想法？

这是在它崩溃之前:

  [06/May/2015:10:47:11 +0200] "GET /ListenerServlet?request=getLastChanged&_=1430852558104 HTTP/1.1" 200 32

崩溃后:

    [06/May/2015:10:47:14 +0200] "GET /ListenerServlet?request=getLastChanged&_=1430902035081 HTTP/1.1" 500 1674

崩溃后,Servlet无法获取请求参数..抛出此nullpointer:

SEVERE: Servlet.service() for servlet [RoomServlet] in context with path [] threw exception java.lang.NullPointerException
        at factory.Factory.initEditMode(Factory.java:37)
        at factory.Factory.init(Factory.java:20)
        at factory.TabsFactory.<init>(TabsFactory.java:19)
        at servlet.RoomServlet.getTabs(RoomServlet.java:285)
        at servlet.RoomServlet.doGet(RoomServlet.java:46)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
        at …

        File file = new File(directory + ".zip");
        if(file.exists()) {
            return;
        }
        url = new URL("http://someURL" +  session);
        is = url.openStream();
        fos = new FileOutputStream(file);
        int data;
        //Leser forbi det første tegnet
        is.read();
        while ((data = is.read()) != -1) {
                fos.write(data);
        }
        is.close();
        fos.close();

当我调用这种方法时,我的程序冻结了20.如何更快地完成这个过程？