Add sequence serializer and deserializer fix #254

src/main/kotlin/com/fasterxml/jackson/module/kotlin/deserializers/SequenceDeserializer.kt

@@ -0,0 +1,14 @@
+package com.fasterxml.jackson.module.kotlin.deserializers
+
+import com.fasterxml.jackson.core.JsonParser
+import com.fasterxml.jackson.databind.DeserializationContext
+import com.fasterxml.jackson.databind.deser.std.StdDeserializer
+
+/**
+ * @author Konstantin Volivach
+ */
+class SequenceDeserializer : StdDeserializer<Sequence<*>>(Sequence::class.java) {
+    override fun deserialize(p: JsonParser, ctxt: DeserializationContext): Sequence<*> {
+        return ctxt.readValue(p, List::class.java).asSequence()
+    }
+}

src/main/kotlin/com/fasterxml/jackson/module/kotlin/serializers/SequenceSerializer.kt

@@ -0,0 +1,14 @@
+package com.fasterxml.jackson.module.kotlin.serializers
+
+import com.fasterxml.jackson.core.JsonGenerator
+import com.fasterxml.jackson.databind.SerializerProvider
+import com.fasterxml.jackson.databind.ser.std.StdSerializer
+
+/**
+ * @author Konstantin Volivach
+ */
+class SequenceSerializer : StdSerializer<Sequence<*>>(Sequence::class.java) {
+    override fun serialize(value: Sequence<*>, gen: JsonGenerator, provider: SerializerProvider) {
+        provider.defaultSerializeValue(value.toList(), gen)
+    }
+}

src/test/kotlin/com/fasterxml/jackson/module/kotlin/test/deserializers/SequenceDeserializerTest.kt

@@ -0,0 +1,37 @@
+package com.fasterxml.jackson.module.kotlin.test.deserializers
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize
+import com.fasterxml.jackson.module.kotlin.KotlinModule
+import com.fasterxml.jackson.module.kotlin.deserializers.SequenceDeserializer
+import com.fasterxml.jackson.module.kotlin.readValue
+import org.junit.Test
+import kotlin.test.assertEquals
+
+/**
+ * @author Konstantin Volivach
+ */
+class SequenceDeserializerTest {
+    data class Data(
+        @field:JsonDeserialize(using = SequenceDeserializer::class)
+        val value: Sequence<String>
+    )
+
+    @Test
+    fun deserializeSequence() {
+        val list = listOf("Test", "Test1")
+        val objectMapper = ObjectMapper()
+        objectMapper.registerModule(KotlinModule())
+        val result = objectMapper.readValue<Data>("{\"value\":[\"Test\",\"Test1\"]}")
+        assertEquals(list, result.value.toList())
+    }
+
+    @Test
+    fun deserializeEmptySequence() {
+        val list = listOf<String>()
+        val objectMapper = ObjectMapper()
+        objectMapper.registerModule(KotlinModule())
+        val result = objectMapper.readValue<Data>("{\"value\":[]}")
+        assertEquals(list, result.value.toList())
+    }
+}

src/test/kotlin/com/fasterxml/jackson/module/kotlin/test/serializers/SequenceSerializerTest.kt

@@ -0,0 +1,42 @@
+package com.fasterxml.jackson.module.kotlin.test.serializers
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import com.fasterxml.jackson.databind.annotation.JsonSerialize
+import com.fasterxml.jackson.module.kotlin.KotlinModule
+import com.fasterxml.jackson.module.kotlin.serializers.SequenceSerializer
+import org.junit.Test
+import kotlin.test.assertEquals
+
+/**
+ * @author Konstantin Volivach
+ */
+class SequenceSerializerTest {
+
+    data class Data(
+        @field:JsonSerialize(using = SequenceSerializer::class)
+        val value: Sequence<String>
+    )
+
+    @Test
+    fun testSerializeSequence() {
+        val sequence = listOf("Test", "Test1").asSequence()
+        val data = Data(
+            sequence
+        )
+        val objectMapper = ObjectMapper()
+        objectMapper.registerModule(KotlinModule())
+        val result = objectMapper.writeValueAsString(data)
+        assertEquals("{\"value\":[\"Test\",\"Test1\"]}", result)
+    }
+
+    @Test
+    fun testSerializeEmptySequence() {
+        val sequence = listOf<String>().asSequence()
+        val data = Data(
+            sequence
+        )
+        val objectMapper = ObjectMapper()
+        val result = objectMapper.writeValueAsString(data)
+        assertEquals("{\"value\":[]}", result)
+    }
+}