Java free native strings (#267)

fundthmcalculus · web-flow · commit ee21e13fffa4 · 2021-11-19T11:11:13.000-07:00
diff --git a/java/src/main/java/ExternError.java b/java/src/main/java/ExternError.java
@@ -1,14 +1,18 @@
+import com.sun.jna.Pointer;
 import com.sun.jna.Structure;
 import com.sun.jna.Structure.FieldOrder;
 
 @FieldOrder({"code", "message"})
 public class ExternError extends Structure {
     public int code;
-    public String message;
+    public Pointer message;
 
     public void RaiseError() throws DidException {
         if (this.code == 0)
             return;
-        throw new DidException(this.code, this.message);
+        // Create the string, then dump the backing store.
+        var messageString = this.message.getString(0, "UTF-8");
+        OkapiNative.getNativeLibrary().okapi_string_free(this.message);
+        throw new DidException(this.code, messageString);
     }
 }
diff --git a/java/src/main/java/OkapiNative.java b/java/src/main/java/OkapiNative.java
@@ -1,4 +1,4 @@
-import com.google.protobuf.*;
+import com.google.protobuf.GeneratedMessageV3;
 import com.sun.jna.Native;
 
 import java.nio.file.Paths;
@@ -37,7 +37,7 @@ public interface IOkapiC extends com.sun.jna.Library {
 
         void okapi_bytebuffer_free(OkapiByteBuffer.ByValue v);
 
-        void okapi_string_free(com.sun.jna.ptr.ByteByReference s);
+        void okapi_string_free(com.sun.jna.Pointer s);
     }
 
     private static IOkapiC nativeLibrary = null;
