文件流读入
import java.util.*;
import java.io.*;
public class Test {
public static void main(String[] args) throws FileNotFoundException
{
Scanner in;
in = new Scanner(new File("1.txt"));
int temp;
for (int i = 0; i < 5; ++i) {
temp = in.nextInt();
System.out.println(temp);
}
}
}
文件流输出
import java.io.*;
public class Test {
public static void main(String[] args) throws IOException {
FileOutputStream fos = new FileOutputStream("2.txt");
OutputStreamWriter osw = new OutputStreamWriter(fos, "UTF-8");
PrintWriter out = new PrintWriter(osw, true);
out.println("Hello world!");
}
}
很有意思的一点是,如果只用了文件名,放到那个类的构造的过程中,那得到的文件是空的!!
这个很有意思!
import java.io.*;
public class Test {
public static void main(String[] args) throws IOException {
FileOutputStream fos = new FileOutputStream("2.txt");
PrintWriter out = new PrintWriter(fos, true);
out.println("Hello world!!");
}
}
上面的代码也是可以的
注意看下这个代码:
import java.io.*;
public class Test {
public static void main(String[] args) throws IOException {
FileOutputStream fos = new FileOutputStream("2.txt");
PrintWriter out = new PrintWriter(fos, false);
out.println("Hello world!!");
}
}
我改成了false,这样的结果,让文件重新变为空的了。