Common exceptions of Java

com.atguigu.java1 Package; 

Import java.io.File; 
Import a java.io.FileInputStream; 
Import java.util.Date; 
Import java.util.Scanner; 

Import org.junit.Test; 

/ * 
* a, the abnormal architecture 
* 
* java.lang.Throwable 
* | ----- java.lang.Error: generally do not write the code targeted for processing. 
* | ----- java.lang.Exception: can perform exception handling 
* | abnormal (checked) ------ compile time 
* | ----- IOException 
* | ----- FileNotFoundException 
* | ClassNotFoundException ----- 
* | ------ runtime exceptions (unchecked, RuntimeException) 
* | ----- NullPointerException 
* | ----- ArrayIndexOutOfBoundsException
* | ----- ClassCastException 
* | ----- NumberFormatException 
* | ----- InputMismatchException 
* | ----- ArithmeticException 
* 
* 
* 
* face questions: What are common abnormalities? Illustrates 
* / 
public class ExceptionTest { 
   
   // The following compile-time exception ************************************************** ***************** ********** 
   @Test 
   public void TEST7 () { 
// File = new new File ( "hello.txt") File; 
// = the FileInputStream new new FIS the FileInputStream (File); 
//     
// int Data fis.read = (); 
// the while (Data = -1!) { 
// of System.out.print ((char) Data); 
// Data fis.read = (); 
//} 
//    
//    fis.close();
      
   }
   
   //******************以下是运行时异常***************************
   //ArithmeticException
   @Test
   public void test6(){
      int a = 10;
      int b = 0;
      System.out.println(a / b);
   }
   
   //InputMismatchException
   @Test
   public void test5(){
      Scanner scanner = new Scanner(System.in);
      int score = scanner.nextInt();
      System.out.println(score);
      
      scanner.close();
   }
   
   //NumberFormatException
   @Test
   public void test4(){
      
      String str = "123";
      str = "abc";
      int num = Integer.parseInt(str);
      
      
      
   }
   
   //ClassCastException
   @Test
   public void test3(){
      Object obj = new Date();
      String str = (String)obj;
   }
   
   //IndexOutOfBoundsException
   @Test
   public void test2(){
      //ArrayIndexOutOfBoundsException
//    int[] arr = new int[10];
//    System.out.println(arr[10]);
      //StringIndexOutOfBoundsException
      String str = "abc";
      System.out.println(str.charAt(3));
   }
   
   //NullPointerException
   @Test
   public void test1(){
      
//    int[] arr = null;
//    System.out.println(arr[3]);
      
      String str = "abc";
      str = null;
      System.out.println(str.charAt(0));
      
   }
   
   
}