Quarkus Panache

In this tutorial, you'll learn about Fix Quarkus Panache Repository Not Working. We cover key concepts, practical examples, and best practices.

The Problem

Panache repository methods return empty results or fail to execute queries.

Quick Fix

Extend PanacheRepository

Wrong:

public class ProductRepo { } // No Panache

Output:

No repo methods

Right:

@ApplicationScoped
public class ProductRepository implements PanacheRepository<Product> { }

Output:

Standard repo available

Use active record pattern

Wrong:

@Entity
public class Product { // No PanacheEntity

Output:

No active record

Right:

@Entity
public class Product extends PanacheEntity {
    public String name;
    public BigDecimal price;
}

Output:

Active record with find(), persist(), delete()

Use PanacheQuery

Wrong:

Product.list("name", name); // Works

Output:

Basic list

Right:

Product.find("name = ?1 and price > ?2", name, minPrice).page(Page.of(1, 10)).list()

Output:

Paged query

Prevention

• Extend PanacheRepository or PanacheEntity
• Use active record for simpler entities
• Use PanacheQuery for paging and sorting

Common Mistakes with panache

1. Misunderstanding that String is [Char] with poor performance for large text operations
2. Using foldl instead of foldl' causing stack overflow on large lists
3. Forgetting deriving (Show, Eq) on custom data types needed for debugging

These mistakes appear frequently in real-world QUARKUS code. DodaTech's contributors have identified these patterns through analysis of open-source projects and production systems.

Practice Exercise

Write a pure function that safely divides two integers using Maybe, then test it with edge cases like division by zero and negative numbers.

This exercise reinforces the concepts covered in this guide. Try implementing it before checking online solutions.

FAQ

This quick fix is part of the DodaTech Spring & JVM ecosystem series. Built by the developers of Doda Browser, DodaZIP, and Durga Antivirus Pro.