1 files changed, 109 insertions, 0 deletions
diff --git a/src/main/java/io/trygvis/esper/testing/util/sql/SqlOption.java b/src/main/java/io/trygvis/esper/testing/util/sql/SqlOption.java
new file mode 100644
index 0000000..286a872
--- /dev/null
+++ b/src/main/java/io/trygvis/esper/testing/util/sql/SqlOption.java
@@ -0,0 +1,109 @@
+package io.trygvis.esper.testing.util.sql;
+
+import java.sql.*;
+
+public abstract class SqlOption<A> {
+    public static <A> SqlOption<A> none() {
+        return new None<>();
+    }
+
+    public static <A> SqlOption<A> some(A a) {
+        return new Some<>(a);
+    }
+
+    public static SqlOption<ResultSet> fromRs(ResultSet rs) throws SQLException {
+        if (!rs.next()) {
+            return none();
+        }
+
+        return some(rs);
+    }
+
+    // -----------------------------------------------------------------------
+    //
+    // -----------------------------------------------------------------------
+
+    public abstract <B> SqlOption<B> map(SqlF<A, B> f) throws SQLException;
+
+    public <B> SqlOption<B> flatMap(SqlF<A, SqlOption<B>> f) throws SQLException {
+        SqlOption<SqlOption<B>> x = map(f);
+
+        if (x.isNone()) {
+            return none();
+        }
+
+        return x.get();
+    }
+
+    public abstract A get() throws SQLException;
+
+    public abstract boolean isSome();
+
+    public boolean isNone() {
+        return !isSome();
+    }
+
+    public abstract A getOrElse(A a);
+
+    public static <A> SqlOption<A> fromNull(A a) {
+        if (a != null) {
+            return some(a);
+        } else {
+            return none();
+        }
+    }
+
+    // -----------------------------------------------------------------------
+    //
+    // -----------------------------------------------------------------------
+
+    private static class None<A> extends SqlOption<A> {
+        public <B> SqlOption<B> map(SqlF<A, B> f) {
+            return none();
+        }
+
+        public A get() throws SQLException {
+            throw new SQLException("get() on None");
+        }
+
+        public boolean isSome() {
+            return false;
+        }
+
+        public A getOrElse(A a) {
+            return a;
+        }
+
+        public String toString() {
+            return "None";
+        }
+    }
+
+    private static class Some<A> extends SqlOption<A> {
+        private final A a;
+
+        private Some(A a) {
+            this.a = a;
+        }
+
+        public <B> SqlOption<B> map(SqlF<A, B> f) throws SQLException {
+            return some(f.apply(a));
+        }
+
+        public A get() {
+            return a;
+        }
+
+        public boolean isSome() {
+            return true;
+        }
+
+        public A getOrElse(A a) {
+            return this.a;
+        }
+
+        public String toString() {
+            return "Some(" + a + ")";
+        }
+    }
+}