文件的基本操作
public class Test {
public static void main(String[] args)
{
File file=new File("hell.txt");
if(file.exists())
{
file.delete();
System.out.println(file.isFile());
System.out.println(file.isDirectory());
}
else {
System.out.println("no exits");
try {
file.createNewFile();
System.out.println("文件已被成功創建");
} catch (IOException e) {
e.printStackTrace();
}
}
}
文件夾
public class Test {
public static void main(String[] args)
{
File folder=new File("new_folder");
File newfolder=new File("new_folder_new");
folder.renameTo(newfolder);
}
File的其他屬性
public class Test {
public static void main(String[] args)
{
File file=new File("test.txt");
System.out.println("判斷文件是否存在"+file.exists());
System.out.println("讀取文件名稱"+file.getName());
System.out.println("讀取文件路徑"+file.getPath());
System.out.println("讀取文件絕對路徑"+file.getAbsolutePath());
System.out.println("獲取文件父級路徑"+new File(file.getAbsolutePath()).getParent());
System.out.println("獲取文件大小"+file.length()+"byte");
System.out.println("判斷文件是否隱藏"+file.isHidden());
System.out.println("判斷文件是否可寫"+file.canWrite());
System.out.println("判斷文件是否可讀"+file.canRead());
System.out.println("判斷文件是否是文件夾"+file.isDirectory());
}
}
File讀寫屬性設置
file.setWritable(true);
file.setReadable(true);
file.setReadOnly();
簡單的文件讀寫
File file=new File("test.txt");
try {
FileInputStream fileInputStream=new FileInputStream(file);
InputStreamReader inputStreamReader=new InputStreamReader(fileInputStream,"UTF-8");
BufferedReader bufferedReader=new BufferedReader(inputStreamReader);
String line=null;
while ((line=bufferedReader.readLine())!=null)
{
System.out.println(line);
}
bufferedReader.close();
inputStreamReader.close();
fileInputStream.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
FileOutputStream fileOutputStream=new FileOutputStream("testnew.txt");
OutputStreamWriter outputStreamWriter=new OutputStreamWriter(fileOutputStream,"UTF-8");
BufferedWriter bufferedWriter=new BufferedWriter(outputStreamWriter);
bufferedWriter.write("hell");
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}