java: throw proper exception on EVMC loader failure

Introduce specific EvmcLoaderException exception.
ethereum · Oct 9, 2020 · 57cccf6 · 57cccf6
1 parent 0a38524
commit 57cccf6
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Showing 4 changed files with 20 additions and 10 deletions.
diff --git a/bindings/java/CMakeLists.txt b/bindings/java/CMakeLists.txt
@@ -11,6 +11,7 @@ add_jar(evmc-jar
     OUTPUT_NAME evmc-java
     VERSION ${PROJECT_VERSION}
     SOURCES
+    java/src/main/java/org/ethereum/evmc/EvmcLoaderException.java
     java/src/main/java/org/ethereum/evmc/EvmcVm.java
     java/src/main/java/org/ethereum/evmc/Host.java
     java/src/main/java/org/ethereum/evmc/HostContext.java

diff --git a/bindings/java/c/evmc-vm.c b/bindings/java/c/evmc-vm.c
@@ -12,12 +12,6 @@
 #include <stdint.h>
 #include <stdlib.h>
 
-static void throw_java_assert(JNIEnv* jenv, const char* msg)
-{
-    jclass jcls = (*jenv)->FindClass(jenv, "java/lang/AssertionError");
-    (*jenv)->ThrowNew(jenv, jcls, msg);
-}
-
 JNIEXPORT jobject JNICALL Java_org_ethereum_evmc_EvmcVm_load_1and_1create(JNIEnv* jenv,
                                                                           jclass jcls,
                                                                           jstring jfilename)
@@ -36,7 +30,9 @@ JNIEXPORT jobject JNICALL Java_org_ethereum_evmc_EvmcVm_load_1and_1create(JNIEnv
     if (loader_error != EVMC_LOADER_SUCCESS)
     {
         const char* error_msg = evmc_last_error_msg();
-        throw_java_assert(jenv, error_msg ? error_msg : "Loading EVMC VM failed");
+        jclass exception_class = (*jenv)->FindClass(jenv, "org/ethereum/evmc/EvmcLoaderException");
+        assert(exception_class != NULL);
+        (*jenv)->ThrowNew(jenv, exception_class, error_msg ? error_msg : "Loading EVMC VM failed");
     }
     jobject jresult = (*jenv)->NewDirectByteBuffer(jenv, (void*)evm, sizeof(struct evmc_vm));
     assert(jresult != NULL);

diff --git a/bindings/java/java/src/main/java/org/ethereum/evmc/EvmcLoaderException.java b/bindings/java/java/src/main/java/org/ethereum/evmc/EvmcLoaderException.java
@@ -0,0 +1,10 @@
+// EVMC: Ethereum Client-VM Connector API.
+// Copyright 2019-2020 The EVMC Authors.
+// Licensed under the Apache License, Version 2.0.
+package org.ethereum.evmc;
+
+public class EvmcLoaderException extends Exception {
+   public EvmcLoaderException(String message) {
+      super(message);
+   }
+}
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
@@ -3,6 +3,7 @@
 // Licensed under the Apache License, Version 2.0.
 package org.ethereum.evmc;
 
+import org.ethereum.evmc.EvmcLoaderException;
 import static org.ethereum.evmc.Host.addContext;
 import static org.ethereum.evmc.Host.removeContext;
 
@@ -22,8 +23,9 @@ public final class EvmcVm implements AutoCloseable {
    * This method loads the specified evm shared library and loads/initializes the jni bindings.
    *
    * @param filename /path/filename of the evm shared object
+   * @throws EvmcLoaderException
    */
-  public static EvmcVm create(String filename) {
+  public static EvmcVm create(String filename) throws EvmcLoaderException {
     if (!EvmcVm.isEvmcLibraryLoaded) {
       try {
         // load so containing the jni bindings to evmc
@@ -40,7 +42,7 @@ public static EvmcVm create(String filename) {
     return evmcVm;
   }
 
-  private EvmcVm(String filename) {
+  private EvmcVm(String filename) throws EvmcLoaderException {
     nativeVm = load_and_create(filename);
   }
 
@@ -49,8 +51,9 @@ private EvmcVm(String filename) {
    *
    * @param Path to the dynamic object representing the EVM implementation.
    * @return Internal object pointer.
+   * @throws EvmcLoaderException
    */
-  private static native ByteBuffer load_and_create(String filename);
+  private static native ByteBuffer load_and_create(String filename) throws EvmcLoaderException;
 
   /**
    * EVMC ABI version implemented by the VM instance.