835
馬士兵J2SE-第八章-流
訪問文件
package com.zzk.test;
import java.io.*;
public class test {
public static void main(String[] args) {
int b=0;
FileInputStream in=null;
try {
in=new FileInputStream("D:\\test\\a\\zzk.txt");
}catch (FileNotFoundException e) {
System.out.println("找不到指定文件");
System.exit(-1);
}
try {
long num=0;
while((b=in.read())!=-1) {
System.out.print((char)b);
num++;
}
in.close();
System.out.println();
System.out.println("共讀取了"+num+"個字節");
}catch(IOException e1) {
System.out.println("文件讀取錯誤");
System.exit(-1);
}
}
}
輸出：
a123123ewawewaq123
asd
ads
adsd
共讀取了31個字節
文件複製：
package com.zzk.test;
//文件複製
import java.io.*;
public class test {
public static void main(String[] args) {
int b = 0;
FileInputStream in = null;
FileOutputStream out = null;
try {
in = new FileInputStream("d:/test/a/zzk.txt");
out = new FileOutputStream("d:/test/a/zzk1.txt");
while((b=in.read())!=-1){
out.write(b);
}
in.close();
out.close();
} catch (FileNotFoundException e2) {
System.out.println("找不到指定文件"); System.exit(-1);
} catch (IOException e1) {
System.out.println("文件複製錯誤"); System.exit(-1);
}
System.out.println("文件已複製");
}
}
import java.io.*;
public class TestFileReader {
public static void main(String[] args) {
FileReader fr = null;
int c = 0;
try {
fr = new FileReader("d:\\share\\java\\io\\TestFileReader.java");
int ln = 0;
while ((c = fr.read()) != -1) {
//char ch = (char) fr.read();
System.out.print((char)c);
//if (++ln >= 100) { System.out.println(); ln = 0;}
}
fr.close();
} catch (FileNotFoundException e) {
System.out.println("找不到指定文件");
} catch (IOException e) {
System.out.println("文件讀取錯誤");
}
}
}
import java.io.*;
public class TestFileWriter {
public static void main(String[] args) {
FileWriter fw = null;
try {
fw = new FileWriter("d:\\bak\\unicode.dat");
for(int c=0;c<=50000;c++){
fw.write(c);
}
fw.close();
} catch (IOException e1) {
e1.printStackTrace();
System.out.println("文件寫入錯誤");
System.exit(-1);
}
}
}
最後更新：2017-04-02 06:52:06