创建文件的方法
方法一
@Test public void create1(){ String filePath = "D:\\file1.txt"; File file = new File(filePath); try { file.createNewFile(); System.out.println("创建文件1成功"); } catch (IOException e) { e.printStackTrace(); } }
方法二
@Test public void create2(){ File parentFile = new File("D:\\"); String fileNane = "file2.txt"; File file = new File(parentFile, fileNane); try { file.createNewFile(); System.out.println("文件2创建成功"); } catch (IOException e) { throw new RuntimeException(e); } }
方法三
@Test public void create3(){ String parentPath = "d:\\"; String filePath = "file3.txt"; File file = new File(parentPath, filePath); try { file.createNewFile(); System.out.println("文件3创建成功"); } catch (IOException e) { throw new RuntimeException(e); } }
获取文件
常见的File相关方法:
getName()/ getAbsolutePath/ getParent/length /exists/ isFile/ isDirectory
public void Info(){ //先创建文件对象 File file = new File("D:\\file1.txt"); //调用相应方法,得到对应信息 System.out.println("文件名称:"+file.getName()); System.out.println("文件绝对路径:"+file.getAbsolutePath()); System.out.println("文件父目录:"+file.getParent()); System.out.println("文件大小(字节):"+file.length()); System.out.println("文件是否存在:"+file.exists()); System.out.println("是否是文件:"+file.isFile()); System.out.println("是否是目录:"+file.isDirectory()); }
目录的操作
//删除文件 public void fileDelete(){ String filePath = "D:\\file1.txt"; File file = new File(filePath); if(file.exists()){ if(file.delete()){ System.out.println(filePath+"删除成功"); }else { System.out.println(filePath+"删除失败"); }; }else{ System.out.println("文件不存在"); } }
//删除目录 @Test public void fileDeleteD(){ String filePath = "D:\\file1.txt"; File file = new File(filePath); if(file.exists()){ if(file.delete()){ System.out.println(filePath+"删除成功"); }else { System.out.println(filePath+"删除失败"); }; }else{ System.out.println("目录不存在"); } }
//判断目录是否存在,不存在就创建 @Test public void fileDeleteD1(){ String dirPath = "D:\\test\\dir1.txt"; File file = new File(dirPath); if(file.exists()){ System.out.println(dirPath+"该目录已经存在"); }else{ if(file.mkdirs()){ System.out.println("创建成功"); }else { System.out.println("创建失败"); }; } }
Scanner与Println
基本键盘输入
import org.testng.annotations.Test; import java.util.Scanner; public class scanPrintTest { public static void main(String[] args) { //创建Scanner对象,接受从控制台输入 Scanner input = new Scanner(System.in); //接受String类型 String str = input.next(); //输出结果 System.out.println(str); System.out.println("hello world"); } }
常见键盘输入类型
import java.util.Scanner; public class scanTest { public static void main(String[] args) { Scanner input =new Scanner(System.in); //double类型的数据 System.out.print("请输入一个double类型的数:"); double d = input.nextDouble(); System.out.println(d); //int类型的数据 System.out.print("请输入一个int类型的数:"); int i = input.nextInt(); System.out.println(i); //字符串类型的数据 System.out.print("请输入一个string类型的数:"); String s = input.next(); System.out.println(s); } }
标签:file,filePath,JavaI,System,File,println,out From: https://www.cnblogs.com/yooouk/p/16863199.html