Kotlin version of a custom condition

Author: jeffgbutler

src/test/kotlin/examples/kotlin/mybatis3/mariadb/KIsLikeEscape.kt

@@ -0,0 +1,44 @@
+package examples.kotlin.mybatis3.mariadb
+
+import org.mybatis.dynamic.sql.AbstractSingleValueCondition
+import org.mybatis.dynamic.sql.BindableColumn
+import org.mybatis.dynamic.sql.render.RenderingContext
+import org.mybatis.dynamic.sql.util.FragmentAndParameters
+import java.util.function.Predicate
+
+open class KIsLikeEscape<T : Any>(value: T, private val escapeCharacter: Char? = null) : AbstractSingleValueCondition<T>(value) {
+
+    override fun operator(): String = "like"
+
+    override fun renderCondition(
+        renderingContext: RenderingContext,
+        leftColumn: BindableColumn<T>
+    ): FragmentAndParameters {
+        val f = super.renderCondition(renderingContext, leftColumn)
+
+        return escapeCharacter?.let { f.mapFragment{ "$it ESCAPE '$escapeCharacter'"} } ?: f
+    }
+
+    override fun filter(predicate: Predicate<in T>): KIsLikeEscape<T> {
+        return filterSupport(predicate, ::empty, this)
+    }
+
+    fun <R : Any> map(mapper : (T) -> R): KIsLikeEscape<R> {
+        return mapSupport(mapper, { r -> KIsLikeEscape(r, escapeCharacter) }, ::empty)
+    }
+
+    private class EmptyCondition : KIsLikeEscape<Any>(-1) {
+        override fun isEmpty(): Boolean = true
+
+        override fun value(): Any {
+            throw NoSuchElementException("No value present") //$NON-NLS-1$
+        }
+    }
+
+    companion object {
+        private val EMPTY: KIsLikeEscape<Any> = EmptyCondition()
+
+        @Suppress("UNCHECKED_CAST")
+        fun <T : Any> empty(): KIsLikeEscape<T> = EMPTY as KIsLikeEscape<T>
+    }
+}