fix: PgDatabaseMetaData: close statement in finally

closes #516
pgjdbc · Jun 22, 2016 · b4c45ca · b4c45ca
1 parent 510e6e0
commit b4c45ca
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Showing 2 changed files with 66 additions and 19 deletions.
diff --git a/pgjdbc/src/main/java/org/postgresql/jdbc/PgDatabaseMetaData.java b/pgjdbc/src/main/java/org/postgresql/jdbc/PgDatabaseMetaData.java
@@ -14,6 +14,7 @@
 import org.postgresql.core.Oid;
 import org.postgresql.core.ServerVersion;
 import org.postgresql.util.GT;
+import org.postgresql.util.JdbcBlackHole;
 import org.postgresql.util.PSQLException;
 import org.postgresql.util.PSQLState;
 
@@ -70,17 +71,21 @@ protected int getMaxIndexKeys() throws SQLException {
             + " t1.typelem=t2.oid AND t1.typname='oidvector'";
       }
       Statement stmt = connection.createStatement();
-      ResultSet rs = stmt.executeQuery(sql);
-      if (!rs.next()) {
-        stmt.close();
-        throw new PSQLException(
-            GT.tr(
-                "Unable to determine a value for MaxIndexKeys due to missing system catalog data."),
-            PSQLState.UNEXPECTED_ERROR);
-      }
-      INDEX_MAX_KEYS = rs.getInt(1);
-      rs.close();
-      stmt.close();
+      ResultSet rs = null;
+      try {
+        rs = stmt.executeQuery(sql);
+        if (!rs.next()) {
+          stmt.close();
+          throw new PSQLException(
+              GT.tr(
+                  "Unable to determine a value for MaxIndexKeys due to missing system catalog data."),
+              PSQLState.UNEXPECTED_ERROR);
+        }
+        INDEX_MAX_KEYS = rs.getInt(1);
+      } finally {
+        JdbcBlackHole.close(rs);
+        JdbcBlackHole.close(stmt);
+      }
     }
     return INDEX_MAX_KEYS;
   }
@@ -95,14 +100,18 @@ protected int getMaxNameLength() throws SQLException {
         sql = "SELECT typlen FROM pg_type WHERE typname='name'";
       }
       Statement stmt = connection.createStatement();
-      ResultSet rs = stmt.executeQuery(sql);
-      if (!rs.next()) {
-        throw new PSQLException(GT.tr("Unable to find name datatype in the system catalogs."),
-            PSQLState.UNEXPECTED_ERROR);
-      }
-      NAMEDATALEN = rs.getInt("typlen");
-      rs.close();
-      stmt.close();
+      ResultSet rs = null;
+      try {
+        rs = stmt.executeQuery(sql);
+        if (!rs.next()) {
+          throw new PSQLException(GT.tr("Unable to find name datatype in the system catalogs."),
+              PSQLState.UNEXPECTED_ERROR);
+        }
+        NAMEDATALEN = rs.getInt("typlen");
+      } finally {
+        JdbcBlackHole.close(rs);
+        JdbcBlackHole.close(stmt);
+      }
     }
     return NAMEDATALEN - 1;
   }

diff --git a/pgjdbc/src/main/java/org/postgresql/util/JdbcBlackHole.java b/pgjdbc/src/main/java/org/postgresql/util/JdbcBlackHole.java
@@ -0,0 +1,38 @@
+package org.postgresql.util;
+
+import java.sql.Connection;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+public class JdbcBlackHole {
+  public static void close(Connection con) {
+    try {
+      if (con != null) {
+        con.close();
+      }
+    } catch (SQLException e) {
+      /* ignore for now */
+    }
+  }
+
+  public static void close(Statement s) {
+    try {
+      if (s != null) {
+        s.close();
+      }
+    } catch (SQLException e) {
+      /* ignore for now */
+    }
+  }
+
+  public static void close(ResultSet rs) {
+    try {
+      if (rs != null) {
+        rs.close();
+      }
+    } catch (SQLException e) {
+      /* ignore for now */
+    }
+  }
+}