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处理大量管道有限档案
原标题:Processing huge pipe delimited files
问题回答

您必须读到逐行文件并写成:

BufferedReader reader = new BufferedReader(new FileReader("foo.txt"));
PrintWriter writer = new PrintWriter(new FileWriter("_foo.txt"));

String line;
boolean firstLine = true;

while ( (line = reader.readLine()) !=null) {
    if (!firstLine) {
        writer.println(line);
        firstLine = false;
    }
}

为了避免重写整个档案,去除一条线,你可以保持档案“启动”指数。 该指数是你认为起点和开始阅读档案的地方。 定期,例如晚上,你可以重写档案,以便“开始”是档案实际开端的地方。

这种“启动”地点可以储存在另一时间或现有档案一开始。

这意味着,你可以逐步“取消”所有档案线,而无需重新撰写。





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