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Java 如何使用缓冲写入器逐行写入文件?_Java_File_Filewriter_Bufferedwriter - Fatal编程技术网

Java 如何使用缓冲写入器逐行写入文件?

Java 如何使用缓冲写入器逐行写入文件?,java,file,filewriter,bufferedwriter,Java,File,Filewriter,Bufferedwriter,下面是我的代码,用于逐行在文件中写入文本 public class TestBufferedWriter { public static void main(String[] args) { // below line will be coming from user and can vary in length. It's just an example String data = "I will write this String to File

下面是我的代码,用于逐行在文件中写入文本

public class TestBufferedWriter {

    public static void main(String[] args) {

        // below line will be coming from user and can vary in length. It's just an example
        String data = "I will write this String to File in Java"; 
        int noOfLines = 100000;

        long startTime = System.currentTimeMillis();
        writeUsingBufferedWriter(data, noOfLines);
        long stopTime = System.currentTimeMillis();
        long elapsedTime = stopTime - startTime;
        System.out.println(elapsedTime);
        System.out.println("process end");

    }


    private static void writeUsingBufferedWriter(String data, int noOfLines) {
        File file = new File("C:/testFile/BufferedWriter.txt");
        FileWriter fr = null;
        BufferedWriter br = null;
        String dataWithNewLine=data+System.getProperty("line.separator");
        try{
            fr = new FileWriter(file);
            br = new BufferedWriter(fr);
            for(int i = 0; i<noOfLines; i++){
                br.write(dataWithNewLine);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }finally{
            try {
                br.close();
                fr.close();

            } catch (Exception e) {

                e.printStackTrace();
            }
        }
    }

}
公共类TestBufferedWriter{
公共静态void main(字符串[]args){
//下面的一行将来自用户,长度可以不同。这只是一个例子
String data=“我将用Java将此字符串写入文件”;
int noOfLines=100000;
long startTime=System.currentTimeMillis();
writeUsingBufferedWriter(数据,noofline);
长停止时间=System.currentTimeMillis();
长延时=停止时间-开始时间;
System.out.println(elapsedTime);
System.out.println(“过程结束”);
}
私有静态void writeUsingBufferedWriter(字符串数据,整数noofline){
File File=新文件(“C:/testFile/BufferedWriter.txt”);
FileWriter fr=null;
BufferedWriter br=null;
字符串dataWithNewLine=data+System.getProperty(“line.separator”);
试一试{
fr=新的文件编写器(文件);
br=新的缓冲写入程序(fr);

对于(int i=0;i您可以在每次调用
br.write(dataWithNewLine);
(在循环内部)之后调用
br.flush()

更简洁的替代方法是使用:

您可以使用
println
写入此文件,就像使用
System.out
一样,它每次都会刷新


这也意味着您不必担心显式追加换行符。

另外:使用try with resources,而不是手动关闭流。您是否可以评论一下BufferedWriter的含义?
PrintWriter pw = new PrintWriter(fr, true);