你有没有掉进去过这些 Exception 的“陷阱“（Part C）

public class ConcurrentModificationExceptionTest {

    List<User> userList = new ArrayList<>();

    @Before
    public void before() {

        User stark = new User();
        stark.setName("stark");
        User thor = new User();
        thor.setName("thor");
        userList.add(stark);
        userList.add(thor);
    }

    @Test
    public void testModifyWhileIteratoringByFor(){

        // 直接使用for循环，触发并发修改异常
        for (User user : userList) {
            if (user.getName().equals("thor")){
                userList.remove(user);
            }
        }
    }
}

@Test
public void testModifyWhileIteratoringByIterator(){

    // 直接使用迭代器
    Iterator<User> iter = userList.iterator();
    while (iter.hasNext()){
        User user = iter.next();
        if (user.getName() == "thor"){
            iter.remove();
        }
    }
}

public class Admin extends User {
}

public class Employee extends User {
}

public class ClassCastExceptionTest {
    
    User employee = new Employee();

    @Test
    public void testCastWithDifferentClass(){
        // 子类之间转换
        Admin admin = (Admin) employee;
    }
}

@Test
public void testUser(){
    Date date = new Date();
    SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
    String simpleDate = simpleDateFormat.format(date);
    System.out.println(simpleDate);

    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM");
    String format = dateFormat.format("");
    System.out.println(format);
}

public enum LoginErrorEnum {
    USERNAME_OR_PASSWORD_NOT_CORRECT,
    NOT_ADMIN_ROLE,
    USERNAME_NOT_REGISTER,
}

public class IllegalArgumentExceptionTest {

    @Test
    public void testGetValueFromEnum(){
        LoginErrorEnum passwordNotCorrect = LoginErrorEnum.valueOf("PASSWORD_NOT_CORRECT");
        System.out.println(passwordNotCorrect);
    }

}

@Test
public void testGetValueFromEnum(){
    try {
        LoginErrorEnum passwordNotCorrect = LoginErrorEnum.valueOf("PASSWORD_NOT_CORRECT");
        System.out.println(passwordNotCorrect);
    } catch (IllegalArgumentException e){
        System.out.println(e.getMessage());
    }
}

<dependency>
    <groupId>com.google.guava</groupId>
    <artifactId>guava</artifactId>
    <version>12.0</version>
</dependency>

@Test
public void testGetValueFromEnumWithGuava(){

    System.out.println(Enums.getIfPresent(LoginErrorEnum.class, "PASSWORD_NOT_CORRECT").orNull());
}

@Test
public void testCloseSingleByTryCatchFinally() throws IOException {
    String context = null;
    BufferedReader bufferedReader = new BufferedReader(new FileReader("info.txt"));
    try {
        context = bufferedReader.readLine();
        System.out.println(context);
    } catch (Exception e){
        System.out.println(e.getMessage());
    } finally {
        bufferedReader.close();
    }
}

@Test
public void testCloseMultiByTryCatchFinally() throws IOException{
    String context = null;
    String message = null;
    BufferedReader bufferedReader = new BufferedReader(new FileReader("info.txt"));
    try {
        context = bufferedReader.readLine();
        BufferedReader messBufferedReader = new BufferedReader(new FileReader("message.txt"));
        try {
            message = messBufferedReader.readLine();
            System.out.println(message);
        } catch (Exception e){
            System.out.println(e.getMessage());
        } finally {
            messBufferedReader.close();
        }
        System.out.println(context);
    } catch (Exception e){
        System.out.println(e.getMessage());
    } finally {
        bufferedReader.close();
    }
}

@Test
public void testCloseSingleByTryWithResources() throws IOException {
    try(BufferedReader reader = new BufferedReader(new FileReader("info.txt"))){
        System.out.println(reader.readLine());
    }
}

@Test
public void testCloseMultiByTryWithResources() throws IOException{
    try(FileInputStream inputStream = new FileInputStream("info.txt");
        FileOutputStream outputStream  = new FileOutputStream("message.txt")) {
         byte[] buffer = new byte[100];
         int n = 0;
         while ((n = inputStream.read(buffer)) != -1){
             outputStream.write(buffer, 0, n);
         }
    }
}

public class LiException extends Exception {

    public LiException() {
        super();
    }

    public LiException(String message) {
        super(message);
    }
}

public class LilithAutoCloseable implements AutoCloseable {


    @Override
    public void close() throws Exception {
        System.out.println("close()方法被调用");
        throw new RuntimeException("close()方法中抛出的异常");
    }

    public void work() throws LiException{
        System.out.println("work()方法被调用");
        throw new LiException("work()方法中抛出的异常");
    }
}

@Test
public void testCloseWithAutoCloseable() throws Exception {

    LilithAutoCloseable lilithAutoCloseable = new LilithAutoCloseable();
    try {
        lilithAutoCloseable.work();
    } finally {
        lilithAutoCloseable.close();
    }
}

@Test
public void testCloseWithAutoCloseableByTryWith() throws Exception {

    try(LilithAutoCloseable lilithAutoCloseable = new LilithAutoCloseable()) {
        lilithAutoCloseable.work();
    }

}