o Initial import of postgresql LISTEN/NOTIFY code.HEADmaster

1 files changed, 44 insertions, 0 deletions

diff --git a/src/main/java/io/trygvis/jz14/db/NativeConnectionSupplier.java b/src/main/java/io/trygvis/jz14/db/NativeConnectionSupplier.java
new file mode 100644
index 0000000..d9db909
--- /dev/null
+++ b/src/main/java/io/trygvis/jz14/db/NativeConnectionSupplier.java
@@ -0,0 +1,44 @@
+package io.trygvis.jz14.db;
+
+import io.trygvis.jz14.db.DbListener.PostgresConnection;
+import org.postgresql.PGConnection;
+
+import javax.sql.DataSource;
+import java.sql.Connection;
+import java.sql.SQLException;
+import java.util.function.Supplier;
+
+public class NativeConnectionSupplier implements Supplier<PostgresConnection<PGConnection>> {
+    private final DataSource dataSource;
+
+    public NativeConnectionSupplier(DataSource dataSource) {
+        this.dataSource = dataSource;
+    }
+
+    @Override
+    public PostgresConnection<PGConnection> get() {
+        try {
+            Connection sqlConnection = dataSource.getConnection();
+            PGConnection pgConnection = unwrap(sqlConnection);
+            return new PostgresConnection<>(sqlConnection, pgConnection);
+        } catch (SQLException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public static PGConnection unwrap(Connection c) {
+        if (c instanceof PGConnection) {
+            return (PGConnection) c;
+        }
+
+        /* If you're using Spring, you need to add these two to properly unwrap the underlying PGConnection.
+        if (c instanceof ConnectionHandle) {
+            return unwrap(((ConnectionHandle) c).getInternalConnection());
+        }
+        if (c instanceof ConnectionProxy) {
+            return unwrap(DataSourceUtils.getTargetConnection(c));
+        }
+        */
+        throw new RuntimeException("Could not unwrap connection to a PGConnection: " + c.getClass());
+    }
+}