java 文件操作相关例子
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
public class FileOperation {
public static void main(String[] args) {
// 新建目录
File folderPath = new File("D:\\ReadFileTest\\FileOperation");
try {
if (!folderPath.exists()) {
folderPath.mkdir(); // 新建目录
}
} catch (Exception e) {
System.out.println("新建目录操作出错");
e.printStackTrace();
}
// 新建文件
File filePath = new File("D:\\ReadFileTest\\FileOperation\\FileOperation.txt");
try {
if (!filePath.exists()) {
filePath.createNewFile(); // 新建文件
}
} catch (Exception e) {
System.out.println("新建文件操作出错");
e.printStackTrace();
}
// // 删除文件
// File delFilePath = new
// File("D:\\ReadFileTest\\FileOperation\\FileOperation.txt");
// try {
// delFilePath.delete();
// } catch (Exception e) {
// System.out.println("删除文件操作出错");
// e.printStackTrace();
// }
// // 删除空文件夹(文件夹不为空不会进行删除)
// File delFolderPath = new File("D:\\ReadFileTest\\FileOperation");
// try {
// delFolderPath.delete(); // 删除空文件夹
// } catch (Exception e) {
// System.out.println("删除文件夹操作出错");
// e.printStackTrace();
// }
// // 删除一个文件夹下所有的文件(夹)
// File delfile = new File("D:\\ReadFileTest\\FileOperation");
// File[] files = delfile.listFiles();
// System.out.println(files.length);
// for (int i = 0; i < files.length; i++) {
// if (!files[i].isDirectory()) {
// files[i].delete();
// }
// }
// FileWriter写文件（无缓冲直接写入）
FileWriter fileWriter = null;
try {
fileWriter = new FileWriter(filePath);
fileWriter.write("test2");
fileWriter.close();
} catch (IOException e) {
System.out.println("写文件操作出错");
e.printStackTrace();
} finally {
if (fileWriter != null) {
try {
fileWriter.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
// FileReader读文件(不能一行行读，只能以一个或指定多个字符读取)
FileReader fileReader = null;
try {
fileReader = new FileReader(filePath);
char[] cbuf = new char[10];
try {
fileReader.read(cbuf);
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("cbuf == " + cbuf[0]); // "t"
} catch (FileNotFoundException e) {
e.printStackTrace();
} finally {
try {
fileReader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// BufferedReader读文件(能一行行读，只能以一个或指定多个字符读取)(拥有8192字符的缓冲区)(以字符流的形式读取数据)
try {
fileReader = new FileReader(filePath);
} catch (FileNotFoundException e1) {
e1.printStackTrace();
}
BufferedReader bufferedReader = new BufferedReader(fileReader);
String readerValue;
try {
while (true) {
readerValue = bufferedReader.readLine();
if (readerValue == null) {
break;
}
System.out.println("readerValue == " + readerValue);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
bufferedReader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// BufferedWriter读文件(不能一行行读，只能以一个或指定多个字符读取)(拥有8192字符的缓冲区)
try {
fileWriter = new FileWriter(filePath);
} catch (IOException e) {
e.printStackTrace();
}
BufferedWriter bufferedWriter = new BufferedWriter(fileWriter);
try {
bufferedWriter.write("hello world !");
bufferedWriter.newLine();
bufferedWriter.newLine();
bufferedWriter.write("!hello world !");
bufferedWriter.write("!hello world !");
// 使用缓冲区中的方法，将数据刷新到目的地文件中去。
bufferedWriter.flush();
// 关闭缓冲区,同时关闭了fw流对象
bufferedWriter.close();
} catch (IOException e) {
e.printStackTrace();
}
// FileInputStream读文件(以字节流的形式读取数据)
FileInputStream fileInputStream = null;
try {
fileInputStream = new FileInputStream(filePath);
try {
int readData = fileInputStream.read();
System.out.println("readData == " + readData);
byte[] b = new byte[2];
fileInputStream.read(b);
System.out.println("b == " + b[0]);
} catch (IOException e) {
e.printStackTrace();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} finally {
try {
fileInputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// FileOutputStream写文件(以字节流的形式写入数据)
FileOutputStream fileOutputStream = null;
try {
fileOutputStream = new FileOutputStream(filePath);
byte[] buf = new byte[] { 96, 0x77, 96 };
try {
fileOutputStream.write(buf);
} catch (IOException e) {
e.printStackTrace();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} finally {
try {
fileOutputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// InputStreamReader字节流向字符流的转换
InputStreamReader inputStreamReader = null;
try {
fileInputStream = new FileInputStream(filePath);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
inputStreamReader = new InputStreamReader(fileInputStream);
char[] charBuf = new char[10];
try {
inputStreamReader.read(charBuf);
System.out.println("charBuf = " + charBuf[0]);
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
inputStreamReader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
// OutputStreamWriter 字节流向字符流的转换
OutputStreamWriter outputStreamWriter = null;
try {
fileOutputStream = new FileOutputStream(filePath);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
outputStreamWriter = new OutputStreamWriter(fileOutputStream);
try {
outputStreamWriter.write("OutputStreamWriter");
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
outputStreamWriter.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
参考原文： http://www.cnblogs.com/chen111/archive/2012/06/16/2551997.html
参考原文： http://uujava0322.iteye.com/blog/1045876
参考原文： http://blog.csdn.net/miyuki0424/article/details/307904
参考原文： http://xyiyy.iteye.com/blog/361476
参考原文： http://blog.csdn.net/liuhenghui5201/article/details/8279557
参考原文： http://blog.sina.com.cn/s/blog_70e5bf6e0101dwsd.html
参考原文： http://blog.csdn.net/liuhenghui5201/article/details/8292552