Test new, print, and free Config works

jvm/src/test/java/org/bitcoindevkit/bdkjni/LibTest.kt

@@ -0,0 +1,43 @@
+package org.bitcoindevkit.bdkjni
+
+import com.sun.jna.Native
+import com.sun.jna.NativeLong
+import org.junit.Test
+
+/**
+ * Library test, which will execute on linux host.
+ *
+ */
+class LibTest {
+
+    private val lib: Lib = Native.load("bdk_ffi", Lib::class.java)
+
+    @Test
+    fun print_string() {
+        lib.print_string("hello print string")
+    }
+
+    @Test
+    fun concat_print_free_string() {
+        val concat = lib.concat_string("hello", "concat")
+        lib.print_string(concat)
+        lib.free_string(concat)
+    }
+    
+    @Test
+    fun print_free_config() {
+        val config = Config_t()
+        config.name = "test"
+        config.count = NativeLong(101)
+        lib.print_config(config)
+        lib.free_config(config)
+    }
+
+    @Test
+    fun new_print_free_config() {
+        println("Long max value = ${Long.MAX_VALUE}")
+        val config = lib.new_config("test test", NativeLong(Long.MAX_VALUE))
+        lib.print_config(config)
+        lib.free_config(config)
+    }
+}