jni: convert C++ exceptions in recognizer/punctuation constructors to Java exceptions (#3988)

An exception escaping a JNI boundary calls std::terminate and aborts the
process. In production we observed an Ort::Exception raised while loading
a corrupt model file inside OfflineRecognizer::newFromFile take down the
whole app, uncatchable from Kotlin.

Wrap every model-loading JNI constructor (offline/online recognizer,
offline/online punctuation, both the file and the asset variants) in a
try/catch that converts the C++ exception into a Java exception via
ThrowNew, following the existing pattern in jni/wave-reader.cc. The
helper RethrowCxxExceptionAsJava lives in jni/common.h.

Fixes #3987

sherpa-onnx/jni/common.h

@@ -5,8 +5,10 @@
 #ifndef SHERPA_ONNX_JNI_COMMON_H_
 #define SHERPA_ONNX_JNI_COMMON_H_
 
+#include <exception>  // NOLINT
 #include <string>
 
+#include "sherpa-onnx/csrc/macros.h"
 #include "sherpa-onnx/csrc/text-utils.h"
 
 #if __ANDROID_API__ >= 9
@@ -223,4 +225,35 @@ namespace sherpa_onnx {
 void PrependAdspLibraryPath(const std::string &new_path);
 }
 
+
+// Convert a C++ exception caught in a JNI function into a Java exception, so
+// callers on the Kotlin/Java side can catch it. Without this, an exception
+// escaping a JNI boundary calls std::terminate and aborts the process (e.g. an
+// Ort::Exception raised while loading a corrupt model file).
+inline void RethrowCxxExceptionAsJava(JNIEnv *env, const std::exception &e,
+                                      const char *context) {
+  SHERPA_ONNX_LOGE("%s: %s", context, e.what());
+  // JNI string functions expect modified UTF-8; an arbitrary what() buffer is
+  // not guaranteed to be valid, and ThrowNew with malformed input is
+  // undefined at the boundary. Fall back to the (ASCII, literal) context when
+  // the message is not printable ASCII, so the Java side always gets a valid
+  // string; the full message is preserved in the log line above.
+  const char *msg = e.what();
+  bool printable = msg[0] != '\0';
+  for (const char *p = msg; *p; ++p) {
+    unsigned char c = static_cast<unsigned char>(*p);
+    if (c < 0x20 || c > 0x7e) {
+      printable = false;
+      break;
+    }
+  }
+  jclass exception_class = env->FindClass("java/lang/Exception");
+  if (exception_class == nullptr) {
+    // FindClass itself failed; nothing more we can do here.
+    return;
+  }
+  env->ThrowNew(exception_class, printable ? msg : context);
+  env->DeleteLocalRef(exception_class);
+}
+
 #endif  // SHERPA_ONNX_JNI_COMMON_H_

sherpa-onnx/jni/offline-punctuation.cc

@@ -63,11 +63,17 @@ Java_com_k2fsa_sherpa_onnx_OfflinePunctuation_newFromAsset(
 
   SHERPA_ONNX_LOGE("config:\n%s", config.ToString().c_str());
 
-  auto model = new sherpa_onnx::OfflinePunctuation(
+  sherpa_onnx::OfflinePunctuation *model = nullptr;
+  try {
+    model = new sherpa_onnx::OfflinePunctuation(
 #if __ANDROID_API__ >= 9
-      mgr,
+        mgr,
 #endif
-      config);
+        config);
+  } catch (const std::exception &e) {
+    RethrowCxxExceptionAsJava(env, e, "Failed to create OfflinePunctuation");
+    return 0;
+  }
 
   return (jlong)model;
 }
@@ -92,7 +98,13 @@ Java_com_k2fsa_sherpa_onnx_OfflinePunctuation_newFromFile(JNIEnv *env,
     return 0;
   }
 
-  auto model = new sherpa_onnx::OfflinePunctuation(config);
+  sherpa_onnx::OfflinePunctuation *model = nullptr;
+  try {
+    model = new sherpa_onnx::OfflinePunctuation(config);
+  } catch (const std::exception &e) {
+    RethrowCxxExceptionAsJava(env, e, "Failed to create OfflinePunctuation");
+    return 0;
+  }
 
   return (jlong)model;
 }

sherpa-onnx/jni/offline-recognizer.cc

@@ -546,7 +546,13 @@ Java_com_k2fsa_sherpa_onnx_OfflineRecognizer_newFromFile(JNIEnv *env,
     return 0;
   }
 
-  auto model = new sherpa_onnx::OfflineRecognizer(config);
+  sherpa_onnx::OfflineRecognizer *model = nullptr;
+  try {
+    model = new sherpa_onnx::OfflineRecognizer(config);
+  } catch (const std::exception &e) {
+    RethrowCxxExceptionAsJava(env, e, "Failed to create OfflineRecognizer");
+    return 0;
+  }
 
   return (jlong)model;
 }

sherpa-onnx/jni/online-punctuation.cc

@@ -68,11 +68,17 @@ Java_com_k2fsa_sherpa_onnx_OnlinePunctuation_newFromAsset(JNIEnv *env,
 
   SHERPA_ONNX_LOGE("config:\n%s", config.ToString().c_str());
 
-  auto model = new sherpa_onnx::OnlinePunctuation(
+  sherpa_onnx::OnlinePunctuation *model = nullptr;
+  try {
+    model = new sherpa_onnx::OnlinePunctuation(
 #if __ANDROID_API__ >= 9
-      mgr,
+        mgr,
 #endif
-      config);
+        config);
+  } catch (const std::exception &e) {
+    RethrowCxxExceptionAsJava(env, e, "Failed to create OnlinePunctuation");
+    return 0;
+  }
 
   return (jlong)model;
 }
@@ -97,7 +103,13 @@ Java_com_k2fsa_sherpa_onnx_OnlinePunctuation_newFromFile(JNIEnv *env,
     return 0;
   }
 
-  auto model = new sherpa_onnx::OnlinePunctuation(config);
+  sherpa_onnx::OnlinePunctuation *model = nullptr;
+  try {
+    model = new sherpa_onnx::OnlinePunctuation(config);
+  } catch (const std::exception &e) {
+    RethrowCxxExceptionAsJava(env, e, "Failed to create OnlinePunctuation");
+    return 0;
+  }
 
   return (jlong)model;
 }

sherpa-onnx/jni/online-recognizer.cc

@@ -273,11 +273,17 @@ Java_com_k2fsa_sherpa_onnx_OnlineRecognizer_newFromAsset(JNIEnv *env,
 #endif
   }
 
-  auto recognizer = new sherpa_onnx::OnlineRecognizer(
+  sherpa_onnx::OnlineRecognizer *recognizer = nullptr;
+  try {
+    recognizer = new sherpa_onnx::OnlineRecognizer(
 #if __ANDROID_API__ >= 9
-      mgr,
+        mgr,
 #endif
-      config);
+        config);
+  } catch (const std::exception &e) {
+    RethrowCxxExceptionAsJava(env, e, "Failed to create OnlineRecognizer");
+    return 0;
+  }
 
   return (jlong)recognizer;
 }
@@ -309,7 +315,13 @@ JNIEXPORT jlong JNICALL Java_com_k2fsa_sherpa_onnx_OnlineRecognizer_newFromFile(
     return 0;
   }
 
-  auto recognizer = new sherpa_onnx::OnlineRecognizer(config);
+  sherpa_onnx::OnlineRecognizer *recognizer = nullptr;
+  try {
+    recognizer = new sherpa_onnx::OnlineRecognizer(config);
+  } catch (const std::exception &e) {
+    RethrowCxxExceptionAsJava(env, e, "Failed to create OnlineRecognizer");
+    return 0;
+  }
 
   return (jlong)recognizer;
 }