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1995fraglet
general-purposeimperativeobject-oriented.java
docker run --rm --platform="linux/amd64" 100hellos/java:latest

MCP + fragletc

MCPstdinargs
This language supports code execution via MCP and the fragletc CLI. Stdin piping and argument passing are both supported.
Install fragletc →

Java is a general-purpose imperative and object-oriented language first appearing in 1995.

Hello World

#!/usr/bin/env sh

set -e

cd /hello-world
javac -cp /lib/wordalytica.jar:. Fraglet.java || exit 1
java -cp /lib/wordalytica.jar:. Fraglet "$@"

Coding Guide

Language Version

Java (OpenJDK)

Execution Model

  • Compiled language
  • The class must be named Fraglet.
  • You must define public static void main(String[] args).

Key Characteristics

  • Statically typed
  • Case-sensitive
  • Object-oriented programming
  • Platform-independent (JVM)
  • Rich standard library

Fragment Authoring

Write a complete Java file: one public class named Fraglet, with your code (imports, main(), and any helper methods or classes).

Available Libraries

  • Java standard library (java.lang, java.util, java.io, etc.)
  • No additional dependencies pre-installed (default mode)

Common Patterns

  • Print: System.out.println("message");
  • Variables: int x = 5; or var x = 5; (Java 10+)
  • Arrays: int[] arr = {1, 2, 3};
  • Lists: List<Integer> list = Arrays.asList(1, 2, 3);
  • String concatenation: "Hello " + name
  • Command-line args: args[0], args.length, String.join(" ", args)

Examples

import java.util.*;

public class Fraglet {
    public static void main(String[] args) {
        System.out.println("Hello, World!");
    }
}
import java.util.*;

public class Fraglet {
    public static void main(String[] args) {
        int a = 5;
        int b = 10;
        int sum = a + b;
        System.out.println("Sum: " + sum);
    }
}
import java.util.*;

public class Fraglet {
    public static void main(String[] args) {
        int[] numbers = {1, 2, 3, 4, 5};
        int sum = 0;
        for (int num : numbers) {
            sum += num;
        }
        System.out.println("Array sum: " + sum);
    }
}
import java.util.*;

public class Fraglet {
    public static int add(int a, int b) {
        return a + b;
    }
    public static void main(String[] args) {
        int result = add(5, 10);
        System.out.println("5 + 10 = " + result);
    }
}
import java.util.*;

public class Fraglet {
    public static void main(String[] args) {
        class Calculator {
            public int multiply(int a, int b) {
                return a * b;
            }
        }
        Calculator calc = new Calculator();
        System.out.println("5 * 3 = " + calc.multiply(5, 3));
    }
}
import java.util.*;

public class Fraglet {
    public static void main(String[] args) {
        System.out.println("Args: " + String.join(" ", args));
    }
}

Caveats

  • Class name must be Fraglet.
  • Must include public static void main(String[] args).
  • Semicolons are required.
  • Case-sensitive.
  • Primitive types vs. wrapper classes (int vs Integer).
  • Array indexing starts at 0.

Fraglet Scripts

Echo Args

#!/usr/bin/env -S fragletc --vein=java
import java.util.*;

public class Fraglet {
    public static void main(String[] args) {
        System.out.println("Args: " + String.join(" ", args));
    }
}

Java Fortune

#!/usr/bin/env -S fragletc --vein=java
import java.util.*;

// One from the vault: Java fortunes
public class Fraglet {
    public static void main(String[] args) {
        System.out.println("Java: the language that made 'enterprise' a four-syllable word.");
    }
}

Stdin Upper

#!/usr/bin/env -S fragletc --vein=java
import java.util.*;

public class Fraglet {
    public static void main(String[] args) {
        java.util.Scanner s = new java.util.Scanner(System.in);
        while (s.hasNextLine()) {
            System.out.println(s.nextLine().toUpperCase());
        }
    }
}

Test

#!/usr/bin/env -S fragletc --vein=java
import java.util.*;

public class Fraglet {
    public static void main(String[] args) {
        System.out.println("Hello World!");
    }
}

Wordalytica Ing Count

#!/usr/bin/env -S fragletc --vein=java --mode=wordalytica
WordSet<?> words = Wordalytica.loadWords();
int n = words.endingWith("ing").count();
System.out.println("Count: " + n);

Wordset

#!/usr/bin/env -S fragletc --vein=java:wordalytica

WordSet<?> words = HelloWorld.loadWords();
int count = words.endingWith("ing").count();
System.out.println("Words ending with 'ing': " + count);

Connections

Container Info

image100hellos/java:latest
build scheduleTuesday
fragletenabled