Tiny fixups

ethereum · Mar 23, 2021 · 5007dea · 5007dea
1 parent 106186d
commit 5007dea
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Showing 2 changed files with 17 additions and 10 deletions.
diff --git a/bindings/java/java/src/main/java/org/ethereum/evmc/EvmcVm.java b/bindings/java/java/src/main/java/org/ethereum/evmc/EvmcVm.java
@@ -18,23 +18,28 @@ public final class EvmcVm implements AutoCloseable {
   private static final Throwable errorLoadingEvmc;
   private ByteBuffer nativeVm;
 
+  // Load the dynamic library containing the JNI bindings to EVMC.
   static {
     Throwable error = null;
+
+    // First try loading from global path.
     try {
-      // Load DLL containing the JNI bindings to EVMC.
       System.loadLibrary("libevmc-java");
-    } catch (UnsatisfiedLinkError e) {
+    } catch (UnsatisfiedLinkError globalLoadingError) {
       String extension = null;
       String os = System.getProperty("os.name").toLowerCase();
       if (os.contains("win")) {
         extension = "dll";
       } else if (os.contains("nix") || os.contains("nux") || os.contains("aix")) {
         extension = "so";
-      } else if (os.contains("mac")|| os.contains("darwin")) {
+      } else if (os.contains("mac") || os.contains("darwin")) {
         extension = "dylib";
       } else {
-        error = e;
+        // Give up, because we are unsure what system we are running on.
+        error = globalLoadingError;
       }
+
+      // Try loading the binding from the package.
       if (extension != null) {
         try {
           Path evmcLib = Files.createTempFile("libevmc-java", extension);
@@ -43,13 +48,14 @@ public final class EvmcVm implements AutoCloseable {
               evmcLib,
               StandardCopyOption.REPLACE_EXISTING);
           evmcLib.toFile().deleteOnExit();
+          // We are somewhat certain about the file, try loading it.
           try {
             System.load(evmcLib.toAbsolutePath().toString());
-          } catch (UnsatisfiedLinkError e1) {
-            error = e1;
+          } catch (UnsatisfiedLinkError packageLoadingError) {
+            error = packageLoadingError;
           }
-        } catch (IOException ex) {
-          error = ex;
+        } catch (IOException packageCreationError) {
+          error = packageCreationError;
         }
       }
     }
@@ -73,7 +79,7 @@ public static boolean isAvailable() {
    */
   public static EvmcVm create(String filename) throws EvmcLoaderException {
     if (!isAvailable()) {
-      throw new EvmcLoaderException("Cannot load EVMC native library", errorLoadingEvmc);
+      throw new EvmcLoaderException("EVMC JNI binding library failed to load", errorLoadingEvmc);
     }
     return new EvmcVm(filename);
   }

diff --git a/bindings/java/java/src/test/java/org/ethereum/evmc/EvmcTest.java b/bindings/java/java/src/test/java/org/ethereum/evmc/EvmcTest.java
@@ -10,9 +10,10 @@
 import org.junit.jupiter.api.Test;
 
 final class EvmcTest {
-  private static final String extension;
   private static final String exampleVmPath;
+
   static {
+    String extension = null;
     String os = System.getProperty("os.name", "generic").toLowerCase();
     if (os.contains("mac") || os.contains("darwin")) {
       extension = "dylib";