The role and usage of throws in java

Thethrows keyword is used to handle exceptions, allowing methods to delegate exceptions to the caller without handling. It identifies the types of exceptions that a method may throw and allows methods to throw exceptions in the method body and delegate exception handling upwards.

The role and usage of throws in Java

The throws keyword is used to handle exceptions in Java, allowing methods Delegate the exception to the method that calls it. This means that the delegated method does not have to handle the exception it catches, but can throw the exception up to be handled by higher-level code.

Function

• Identifies the types of exceptions that may be thrown by a method
• Allows a method to delegate an exception to the method that calls it instead of handling it It

Usage

#1. Declare exceptions in method declaration

public void doSomething() throws IOException, SQLException {
    // 方法体
}

Use throws in method declaration The keyword followed by the exception type indicates that the method may throw these types of exceptions. The code calling the method must handle these exceptions or delegate them further.

2. Throw an exception in the method body

try {
    // 执行一些操作
} catch (IOException | SQLException e) {
    throw e;
}

In the method body, you can throw an exception by using the throw keyword followed by the exception object. This will cause the exception to be delegated to the code that calls the method.

Advantages

• ##Better exception handling: throws improves performance by allowing methods to clearly identify exceptions that may occur based on their logic Improved exception handling clarity.
• More flexible exception delegation: Instead of explicitly rethrowing an exception, a method can delegate the exception to the method that called it, thus simplifying exception handling.
• Reducing the burden on the caller: The code calling the method does not have to handle its unrelated exception because it can be handled at a higher level.

Note:

Only the checked exception type thrown by a method needs to be declared in the method declaration.
• Runtime exceptions do not need to be declared in the method declaration because they do not need to be handled explicitly.
• Avoid overuse of throws and only use exceptions when you need to delegate them to the caller.

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