How do I compile and run these Java programs?

Install a JDK, compile with javac Main.java, then run with java Main.

Which Java version are these examples compatible with?

Examples target Java 8+, including lambdas and streams.

Can I safely copy and modify the examples?

Yes. Copy, modify inputs, and observe outputs to reinforce concepts.

Do these programs work on all platforms?

Programs compile and run on Windows, macOS, and Linux with a standard JDK.

String Handling and Text Processing

Work with strings—split, join, count words, check uniqueness, and compute frequencies. Practical text processing tasks you will use daily.

Java Program to Reverse a String

Program (Java)

Example & Expected Output

Reverses a string using StringBuilder.

avaJ

Program Output

Java Program to Check Palindrome String

Program (Java)

Example & Expected Output

Checks if a string reads the same forwards and backwards.

true

Program Output

Java Program to Split and Join Strings

Program (Java)

Example & Expected Output

Splits by spaces and joins with commas.

Java,is,fun

Program Output

Java Program to Count Words in a String

Program (Java)

Example & Expected Output

Counts words by splitting on whitespace.

Program Output

Java Program to Check If Two Strings Are Anagrams

Program (Java)

Example & Expected Output

Checks anagram by sorting characters.

true

Program Output

Java Program to Check Unique Characters in String

Program (Java)

Example & Expected Output

Detects if all characters are unique.

true

Program Output

Java Program to Compute Word Frequency

Program (Java)

Example & Expected Output

Counts word occurrences in a sentence.

{to=2, be=2, or=1, not=1}

Program Output

Frequently Asked Questions

Install a JDK (Java Development Kit), then compile with javac Main.java and run with java Main. On macOS, Linux, or Windows, use the official OpenJDK builds or your package manager.

The examples target modern Java (Java 8 and above). If you use older versions, most examples will still work, but features like lambdas and streams require Java 8+.

Yes. These examples are intended for learning. Copy the code, experiment with changes (e.g., different inputs), and observe the output to deepen your understanding of Java fundamentals.

Yes. Java is platform-independent. The examples compile and run on major platforms (Windows, macOS, Linux) with a standard JDK.

Learn Java the Practical Way

Java powers enterprise applications, Android development, and countless backend systems. Practicing small, focused programs builds fluency with syntax and core concepts such as data types, control flow, methods, classes, interfaces, exceptions, collections, and streams.

On this page, you will find clean, well-formatted examples that run across platforms. Each example includes a short description and expected output so you can quickly verify your understanding. Explore the topics via the sidebar and extend the code to experiment further.

Whether you are preparing for interviews, working through coursework, or refreshing fundamentals, these examples offer a practical path to mastering Java. Bookmark the page and return often to keep improving.