Update LimboDB.java to load libraries from /lib

bindings/java/src/main/java/org/github/tursodatabase/core/LimboDB.java

@@ -2,6 +2,10 @@ package org.github.tursodatabase.core;
 
 import static org.github.tursodatabase.utils.ByteArrayUtils.stringToUtf8ByteArray;
 
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
 import java.sql.SQLException;
 import java.util.concurrent.locks.ReentrantLock;
 import org.github.tursodatabase.LimboErrorCode;
@@ -30,17 +34,136 @@ public final class LimboDB extends AbstractDB {
     }
   }
 
-  /** Loads the SQLite interface backend. */
+  /**
+   * Enum representing different architectures and their corresponding library paths and file
+   * extensions.
+   */
+  enum Architecture {
+    MACOS_ARM64("libs/macos_arm64/lib_limbo_java.dylib", ".dylib"),
+    MACOS_X86("libs/macos_x86/lib_limbo_java.dylib", ".dylib"),
+    WINDOWS("libs/windows/lib_limbo_java.dll", ".dll"),
+    UNSUPPORTED("", "");
+
+    private final String libPath;
+    private final String fileExtension;
+
+    Architecture(String libPath, String fileExtension) {
+      this.libPath = libPath;
+      this.fileExtension = fileExtension;
+    }
+
+    public String getLibPath() {
+      return libPath;
+    }
+
+    public String getFileExtension() {
+      return fileExtension;
+    }
+
+    public static Architecture detect() {
+      String osName = System.getProperty("os.name").toLowerCase();
+      String osArch = System.getProperty("os.arch").toLowerCase();
+
+      if (osName.contains("mac")) {
+        if (osArch.contains("aarch64") || osArch.contains("arm64")) {
+          return MACOS_ARM64;
+        } else if (osArch.contains("x86_64") || osArch.contains("amd64")) {
+          return MACOS_X86;
+        }
+      } else if (osName.contains("win")) {
+        return WINDOWS;
+      }
+
+      return UNSUPPORTED;
+    }
+  }
+
+  /**
+   * This method attempts to load the native library required for Limbo operations. It first tries
+   * to load the library from the system's library path using {@link #defaultLoad()}. If that fails,
+   * it attempts to load the library from the JAR file using {@link #loadFromJar()}. If either
+   * method succeeds, the `isLoaded` flag is set to true. If both methods fail, an {@link
+   * InternalError} is thrown indicating that the necessary native library could not be loaded.
+   *
+   * @throws InternalError if the native library cannot be loaded from either the system path or the
+   *     JAR file.
+   */
   public static void load() {
     if (isLoaded) {
       return;
     }
 
+    if (defaultLoad() || loadFromJar()) {
+      isLoaded = true;
+      return;
+    }
+
+    throw new InternalError("Unable to load necessary native library");
+  }
+
+  /**
+   * Load the native library from the system path.
+   *
+   * <p>This method attempts to load the native library named "_limbo_java" from the system's
+   * library path. If the library is successfully loaded, the `isLoaded` flag is set to true.
+   *
+   * @return true if the library was successfully loaded, false otherwise.
+   */
+  private static boolean defaultLoad() {
     try {
       System.loadLibrary("_limbo_java");
-    } finally {
-      isLoaded = true;
+      return true;
+    } catch (Throwable t) {
+      logger.info("Unable to load from default path: {}", String.valueOf(t));
     }
+
+    return false;
+  }
+
+  /**
+   * Load the native library from the JAR file.
+   *
+   * <p>By default, native libraries are packaged within the JAR file. This method extracts the
+   * appropriate native library for the current operating system and architecture from the JAR and
+   * loads it.
+   *
+   * @return true if the library was successfully loaded, false otherwise.
+   */
+  private static boolean loadFromJar() {
+    Architecture arch = Architecture.detect();
+    if (arch == Architecture.UNSUPPORTED) {
+      logger.info("Unsupported OS or architecture");
+      return false;
+    }
+
+    try {
+      InputStream is = LimboDB.class.getClassLoader().getResourceAsStream(arch.getLibPath());
+      assert is != null;
+      File file = convertInputStreamToFile(is, arch);
+      System.load(file.getPath());
+      return true;
+    } catch (Throwable t) {
+      logger.info("Unable to load from jar: {}", String.valueOf(t));
+    }
+
+    return false;
+  }
+
+  private static File convertInputStreamToFile(InputStream is, Architecture arch)
+      throws IOException {
+    File tempFile = File.createTempFile("lib", arch.getFileExtension());
+    tempFile.deleteOnExit();
+
+    try (FileOutputStream os = new FileOutputStream(tempFile)) {
+      int read;
+      byte[] bytes = new byte[1024];
+
+      while ((read = is.read(bytes)) != -1) {
+        os.write(bytes, 0, read);
+      }
+    }
+
+    return tempFile;
   }
 
   /**