JAVA 文件输入/输出流

package cn.com.file;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

/**
* FileInputStream类与FileOutputStream类<br>
* 文件读与写
* @author wutz
*
*/
public class FileTest {

public static void main(String[] args) {
//1.先往文件中写入数据
try {
FileOutputStream out = new FileOutputStream(new File("C:/Users/wutz/Desktop/j2se/resource/test.txt"));
byte[] bt = "测试写入文件".getBytes();
out.write(bt);
out.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

//2.从文件中读取数据到控制台
try {
FileInputStream in = new FileInputStream(new File("C:/Users/wutz/Desktop/j2se/resource/test.txt"));
byte[] bt1 = new byte[1024];
int lenth = in.read(bt1);
System.out.println("文件中的信息是："+ new String(bt1,0,lenth));
in.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

}
}

package cn.com.file;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

/**
* FileWriter类与FileReader类<br>
* 文件读与写（处理字符流）
* @author wutz
*
*/
public class FileTest {

public static void main(String[] args) {
//1.先往文件中写入数据
try {
FileWriter out = new FileWriter(new File("C:/Users/wutz/Desktop/j2se/resource/test.txt"));
String s = new String("测试FileWriter"
+ "123阿萨德");
out.write(s);
out.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}

//2.从文件中读取数据到控制台
try {
FileReader in = new FileReader(new File("C:/Users/wutz/Desktop/j2se/resource/test.txt"));
char[] ch = new char[1024];
int lenth = in.read(ch);
System.out.println("文件中的信息是："+ new String(ch,0,lenth));
in.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}