Some tricky programs in Java

Confusing Java problems arise from loops, multithreading, overloading, overriding, etc., making them difficult to navigate.

Sometimes, seemingly simple problems confuse us, causing us to write disorganized code instead of direct solutions.

Through analytical thinking, we can solve these problems even without prior knowledge. Join us as we explore tricky programs in Java.

usage instructions

• Valid comment

• Named Loop

Method 1: Valid Comments

In the field of programming, Java comments are text statements in the program that have no meaning when executed by the compiler or interpreter.

The purpose of incorporating comments into code is multifaceted. They are valuable tools for enhancing code readability, allowing developers to provide more insights into the complexity of a program.

Comments contribute to the ease of code maintenance and facilitate the identification of errors by providing clear explanations and relevant details. Additionally, comments can provide valuable information about a variable, method, class, or any given statement in your code base.

Additionally, they can be used as a way to selectively disable execution of specific sections of code, especially when exploring alternative code paths during testing and experimentation.

However, let’s dive into a fascinating concept today: “actionable comments.”

Program 1

This code prints a comment using Unicode characters.

algorithm

Step 1: Declare the "Tutorialspoint" public class.

Step 2: Define the main method as "public static void main(String[] args)".

Step 3: Start executing the main method.

Step 4: Add a single-line comment before the next line of code to indicate that this line of code will produce output.

Step 5: As a comment, use the Unicode character u000d, which represents the carriage return character.

Step 6: Use the System.out.println() method to print the string "comment has been executed".

Example

public class Tutorialspoint {
    public static void main(String[] args)
	{
		// the code line below this provides an output
		// \u000d
		System.out.println("comment has been executed");
	}
}

Output

comment has been executed

Note: An interesting property of this code is the comment using the Unicode character \u000d, which is interpreted by the Java compiler as a new line. Contrary to the expected comments, the following lines of code will be executed.

Method 2: Named loop

In Java programming, named loops are not an inherent part of the language standard library. Java's looping mechanism usually revolves around conditional and iteration variables to monitor loop progress. However, utilizing flags or tags can circumvent the lack of naming cycles and provide a viable alternative.

for()

This Java program demonstrates the use of named loops. It has two nested loops labeled "loop1" and prints the values ​​of variables i and j. When i equals 4, the named loop is broken and the program exits the loop. The output shows the i and j values ​​for each iteration until the breaking condition is met.

algorithm

Step 1: Declare a class named Tutorialspoint.

Step 2: Define the main method as the entry point of the program.

Step 3: Use the initialization of i as 1 to start the outer loop labeled loop1.

Step 4: Check if the value of i is less than 7.

Step 5: If the condition is true, enter the outer loop.

Step 6: Start the inner loop, j is initialized to 2.

Step 7: Check whether the value of j is less than 8.

Step 8: If the condition is true, enter the inner loop.

Step 9: Check whether the value of i is 4.

Step 10: If the condition is true, jump out of the outer loop marked loop1.

Step 11: If the condition is false, execute the statement inside the if block.

Step 12: Use the println statement to print the values ​​of i and j.

Step 13: Increase the value of j by 1.

Step 14: Return to step 8.

Step 15: If the condition in step 8 is false, you must exit the inner loop.

Step 16: Increase the value of i by 1.

Step 17: Now return to step 5.

Step 18: If the condition in step 5 is false, exit the outer loop.

Example

// A Java program to explain how named loops work.
public class Tutorialspoint
{
    public static void main(String[] args)
	{
	loop1:
	for (int i = 1; i < 3; i++)
	{
		for (int j = 2; j < 4; j++)
		{
			if (i == 4)
				break loop1;
			System.out.println("i = " + i + " j = " + j);
		}
	}
    }
}

Output

i = 1 j = 2
i = 1 j = 3
i = 2 j = 2
i = 2 j = 3

in conclusion

Java programming often requires dealing with loops, multi-threading, overloading and rewriting, etc. These challenges sometimes result in large and complex code rather than simple answers. However, with analytical thinking and problem-solving skills, these problems can be overcome even without previous expertise.

In this blog, we explore two approaches: leveraging annotations for execution, and leveraging named loops to achieve more precise control over loop behavior. Developers can improve code readability, maintainability, and overall program effectiveness by employing these techniques.

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