Java對大檔案的高效讀取方法
阿新 • • 發佈：2019-01-22
1、檔案流
現在讓我們看下這種解決方案——我們將使用java.util.Scanner類掃描檔案的內容，一行一行連續地讀取：
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FileInputStream inputStream
= null;
Scanner sc = null;
try {
inputStream
= new FileInputStream(path);
sc
= new Scanner(inputStream, "UTF-8");
while (sc.hasNextLine())
{
String line
= sc.nextLine();
//
System.out.println(line);
}
//
note that Scanner suppresses exceptions
if (sc.ioException()
!= null)
{
throw sc.ioException();
}
} finally {
if (inputStream
!= null)
{
inputStream.close();
}
if (sc
!= null)
{
sc.close();
}
}
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2、Apache Commons IO流
同樣也可以使用Commons IO庫實現，利用該庫提供的自定義LineIterator:
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LineIterator it = FileUtils.Iterator(theFile, "UTF-8");
try {
while (it.hasNext())
{
String
line = it.nextLine();
//
do something with line
}
} finally {
LineIterator.closeQuietly(it);
}
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