8 Java Programming Tricks Every Java Developer Should Know

Developer Nation
5 min readMay 29


A blog shared by Daria Minkevich in our Developer Nation Community.

Java is one of the most popular programming languages in the programming world, used by millions of developers to build complex software systems and applications. As a Java developer, it’s essential to stay up-to-date with the latest trends and techniques to remain competitive and produce high-quality code. In this article, we’ll explore eight Java programming tricks every Java developer should know, including how java developers for hire can help you implement them in your projects.

  • Use Lambda Expressions

Lambda expressions are a powerful feature introduced in Java 8 that allow you to write functional-style code with less boilerplate. With lambda expressions, you can define a method as a parameter to another method, reducing the amount of code you need to write. For example, instead of writing:

List<String> names = new ArrayList<>(); for (Person person : people) { names.add(person.getName()); }

You can use a lambda expression like this:

List<String> names = people.stream() .map(Person::getName) .collect(Collectors.toList());

This code is more concise and easier to read, making your code more maintainable.

  • Use Optional Instead of Nulls

Nulls can cause many problems in Java code, including NullPointerExceptions, which can be difficult to debug. Instead of using nulls, use the Optional class, which allows you to represent an object that may or may not be present. Optional provides a safer and more elegant way to handle nulls in your code.

  • Use Streams for Collection Operations
    Streams provide a concise and powerful way to perform operations on collections in Java. With streams, you can perform operations like filtering, mapping, and reducing without the need for complex loops or temporary collections. Streams can significantly simplify your code and make it easier to read and maintain.
  • Use String.format for String Concatenation
    String concatenation can be a performance bottleneck in Java code, especially when concatenating large strings. Instead of using the + operator, use the String.format method to concatenate strings. String.format creates a formatted string that you can customize with placeholders and arguments, making your code more readable and efficient.
public class StrFormat { /* Driver Code */ public static void main(String args[]) { String s1 = new String("Hello"); //String 1 String s2 = new String(" World"); //String 2 String s = String.format("%s%s",s1,s2); //String 3 to store the result System.out.println(s.toString()); //Displays result } }
  • Use Immutable Objects

Immutable objects are objects whose state cannot be changed after creation. Immutable objects are thread-safe and can simplify your code by eliminating the need for locks or synchronization. Use immutable objects whenever possible to improve the performance and reliability of your code.

String name = "baeldung"; String newName = name.replace("dung", "----"); assertEquals("baeldung", name); assertEquals("bael----", newName);
  • Use Interface Default Methods

Default methods were introduced in Java 8 and allow you to add methods to an interface without breaking existing implementations. Default methods provide a powerful way to extend existing interfaces and create more flexible and maintainable code.

import java.time.*; public interface TimeClient { void setTime(int hour, int minute, int second); void setDate(int day, int month, int year); void setDateAndTime(int day, int month, int year, int hour, int minute, int second); LocalDateTime getLocalDateTime(); }
  • Use Reflection Sparingly

Reflection is a powerful but dangerous feature in Java that allows you to inspect and modify the behaviour of a program at runtime. Reflection can be slow and error-prone, and should only be used when necessary. If possible, use other features of Java, such as interfaces, to achieve your goals.

import java.lang.reflect.*; public class DumpMethods { public static void main(String args[]) { try { Class c = Class.forName(args[0]); Method m[] = c.getDeclaredMethods(); for (int i = 0; i < m.length; i++) System.out.println(m[i].toString()); } catch (Throwable e) { System.err.println(e); } } }
  • Use Enumerations Instead of Constants

Enumerations are a more powerful and flexible way to represent constants in Java. Enumerations allow you to group related constants and define their behaviour, making your code more expressive and maintainable. Use enumerations whenever possible to avoid the problems associated with traditional constants.

public class Main { enum Level { LOW, MEDIUM, HIGH } public static void main(String[] args) { Level myVar = Level.MEDIUM; System.out.println(myVar); } }
  • Use Try-With-Resources for Resource Management
    Try-With-Resources is a feature introduced in Java 7 that allows you to automatically close resources such as files, sockets, and database connections after they are no longer needed. Try-With-Resources can simplify your code and ensure that resources are always properly closed, reducing the risk of resource leaks and other problems.
  • Use Javadoc to Document Your Code
    Javadoc is a powerful tool for documenting your Java code. With Javadoc, you can create professional-looking documentation for your code that can be easily shared with other developers. Javadoc can also help you understand your own code better and identify potential problems and bugs.
  • Use Dependency Injection for Loose Coupling
    Dependency Injection is a design pattern that promotes loose coupling between components of a system. With Dependency Injection, you can inject dependencies into a class instead of creating them inside the class, reducing the complexity and dependencies of your code. Dependency Injection can also make your code more flexible and easier to test, making it a valuable technique for Java developers to learn.

Use Unit Testing for Quality Assurance

Unit Testing is a crucial technique for ensuring the quality and correctness of your Java code. With Unit Testing, you can test individual units of code in isolation, identifying and fixing problems before they become larger issues. Unit Testing can also improve the maintainability of your code by ensuring that changes and updates don’t introduce unexpected side effects or bugs. As a Java developer, it’s essential to understand and practise Unit Testing to produce high-quality, reliable code.


Java developers for hire can help you implement these programming tricks in your projects. The tricks we mentioned can improve the quality and efficiency of your code, and help you stay up-to-date with the latest trends and techniques in Java programming. But if you need to do it asap, Java developers for hire can help you implement these programming tricks in your projects.



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