From try-with-resources to ThreadLocal, optimize how you write your code

1. Use try-with-resources to simplify file reading operations:

Before modification:

FileInputStream fis = null;
try {
    fis = new FileInputStream("");
    // ...
} catch (FileNotFoundException e) {
    ();
} finally {
    if (fis != null) {
        try {
            ();
        } catch (IOException e) {
            ();
        }
    }
}

After modification:

try (FileInputStream fis = new FileInputStream("")) {
    // ...
} catch (IOException e) {
    ();
}

2. Use Lambda expressions to simplify collection operations:

Before modification:

List<String> names = ("Alice", "Bob", "Charlie");
for (String name : names) {
    (name);
}

After modification:

List<String> names = ("Alice", "Bob", "Charlie");
(name -> (name));

3. Use the StringBuilder class to splice strings:

Before modification:

String s = "";
for (int i = 0; i < 10; i++) {
    s += i;
}

After modification:

StringBuilder sb = new StringBuilder();
for (int i = 0; i < 10; i++) {
    (i);
}
String s = ();

4. Use static import to simplify the code:

Before modification:

((2));

After modification:

import static ;
(sqrt(2));

5. Use assertions to simplify debugging:

Before modification:

if (x < 0) {
    throw new IllegalArgumentException("x must be non-negative");
}

After modification:

assert x >= 0 : "x must be non-negative";

6. Use the Optional class to handle objects that may be empty:

Before modification:

String s = null;
if (s != null) {
    (());
}

After modification:

Optional<String> optional = (null);
(s -> (()));

7. Use enumeration classes to replace constants:

Before modification:

public static final int STATUS_NEW = 0;
public static final int STATUS_PROCESSING = 1;
public static final int STATUS_COMPLETED = 2;

After modification:

public enum Status {
    NEW,
    PROCESSING,
    COMPLETED
}

8. Use a custom exception class to replace the general exception class:

Before modification:

try {
    // ...
} catch (Exception e) {
    ();
}

After modification:

try {
    // ...
} catch (MyCustomException e) {
    ();
}

9. Simplify collection operations using Lambda expressions and Stream API:

Before modification:

List<Integer> numbers = (1, 2, 3, 4, 5);
List<Integer> evenNumbers = new ArrayList<>();
for (int number : numbers) {
    if (number % 2 == 0) {
        (number);
    }
}

After modification:

List<Integer> numbers = (1, 2, 3, 4, 5);
List<Integer> evenNumbers = ()

10. Use ThreadLocal to avoid thread safety issues:

Before modification:

public class MyRunnable implements Runnable {
    private int count = 0;
    public void run() {
        for (int i = 0; i &lt; 100000; i++) {
            count++;
        }
        (count);
    }
}

After modification:

public class MyRunnable implements Runnable {
    private ThreadLocal<Integer> count = new ThreadLocal<Integer>() {
        @Override
        protected Integer initialValue() {
            return 0;
        }
    };
    public void run() {
        for (int i = 0; i < 100000; i++) {
            (() + 1);
        }
        (());
    }
}

In a multi-threaded environment, using ordinary member variables will cause thread safety problems, while using ThreadLocal can ensure that the variables accessed by each thread are independent, avoiding thread safety problems. In the example above, using ThreadLocal ensures that the count variables accessed by each thread are independent, thus avoiding thread safety issues.

The above is the detailed content of optimizing your code writing method from try-with-resources to ThreadLocal. For more information about trying-with-resources ThreadLocal optimization code, please follow my other related articles!