A foundational Java library providing essential utilities and components for the CodeLibs project ecosystem. Built with Java 21 and optimized for modern Java development patterns including pattern matching, switch expressions, and sequenced collections.

## ✨ Features

### Core Utilities

      this.columnComparator = checkNotNull(columnComparator, "columnComparator");
      return this;
    }

    /**
     * Associates the ({@code rowKey}, {@code columnKey}) pair with {@code value} in the built
     * table. Duplicate key pairs are not allowed and will cause {@link #build} to fail.
     */
    @CanIgnoreReturnValue
    public Builder<R, C, V> put(R rowKey, C columnKey, V value) {

 * weight = 1 + max(downstream_project_weights)
 *
 * <p>Projects are then sorted by weight in descending order, ensuring that
 * projects with longer dependency chains are built first. When projects have
 * the same weight, they are ordered by project ID for deterministic results.
 *
 * <p><b>Example:</b>
 * <p>Consider projects with dependencies: A → B → D, A → C → D
 * <ul>

   *
   * For OPTIONS requests, this may be an asterisk, `*`.
   */
  public val target: String,
  /** A string like `HTTP/1.1` or `HTTP/2`. */
  public val version: String,
  /** The request URL built using the request line, headers, and local host name. */
  public val url: HttpUrl,
  /** All headers. */
  public val headers: Headers,
  /** The body of this request, or null if it has none. This may be truncated. */

     *
     * @return the start time as an Instant object, never {@code null}
     */
    @Nonnull
    Instant getStartTime();

    /**
     * Gets the directory of the topmost project being built, usually the current directory or the
     * directory pointed at by the {@code -f/--file} command line argument.
     *
     * @return the directory of the topmost project, never {@code null}
     * @see Project#isTopProject()

     * ImmutableBiMap#builder}.
     */
    public Builder() {}

    Builder(int size) {
      super(size);
    }

    /**
     * Associates {@code key} with {@code value} in the built bimap. Duplicate keys or values are
     * not allowed, and will cause {@link #build} to fail.
     */
    @CanIgnoreReturnValue
    @Override
    public Builder<K, V> put(K key, V value) {

It is also commonly used for other applications that don't necessarily need a database, user management, or any of the many features that come pre-built in Django. Although many of these features can be added with plug-ins.

This decoupling of parts, and being a "microframework" that could be extended to cover exactly what is needed was a key feature that I wanted to keep.

public final class HostSpecifier {

  private final String canonicalForm;

  private HostSpecifier(String canonicalForm) {
    this.canonicalForm = canonicalForm;
  }

  /**
   * Returns a {@code HostSpecifier} built from the provided {@code specifier}, which is already
   * known to be valid. If the {@code specifier} might be invalid, use {@link #from(String)}
   * instead.
   *
   * <p>The specifier must be in one of these formats:
   *

Each section gradually builds on the previous ones, but it's structured to separate topics, so that you can go directly to any specific one to solve your specific API needs.

It is also built to work as a future reference so you can come back and see exactly what you need.

## Run the code { #run-the-code }

All the code blocks can be copied and used directly (they are actually tested Python files).

import java.nio.file.Files;
import java.util.HashSet;
import java.util.Set;

/**
 * A custom archive task that assembles a tar archive that preserves symbolic links.
 *
 * This task is necessary because the built-in task {@link org.gradle.api.tasks.bundling.Tar} does not preserve symbolic links.
 */
public class SymbolicLinkPreservingTar extends Tar {

    @Override
    protected CopyAction createCopyAction() {