Fix SQLServerDatabaseMetadata.getMaxConnections() API query

src/main/java/com/microsoft/sqlserver/jdbc/SQLServerDatabaseMetaData.java

@@ -28,6 +28,7 @@
  * The API javadoc for JDBC API methods that this class implements are not repeated here. Please see Sun's JDBC API
  * interfaces javadoc for those details.
  */
+@SuppressWarnings("unused")
 public final class SQLServerDatabaseMetaData implements java.sql.DatabaseMetaData, Serializable {
     /**
      * Always update serialVersionUID when prompted.
@@ -1014,16 +1015,23 @@ public int getMaxColumnsInTable() throws SQLServerException {
     @Override
     public int getMaxConnections() throws SQLException, SQLTimeoutException {
         checkClosed();
-        try {
-            String s = "sp_configure 'user connections'";
-            SQLServerResultSet rs = getResultSetFromInternalQueries(null, s);
-            if (!rs.next())
+        try (SQLServerResultSet rs = getResultSetFromInternalQueries(null,
+                "select maximum from sys.configurations where name = 'user connections'")) {
+            if (!rs.next()) {
                 return 0;
+            }
             return rs.getInt("maximum");
         } catch (SQLServerException e) {
-            return 0;
+            // Try with sp_configure if users do not have privileges to execute sys.configurations
+            try (SQLServerResultSet rs1 = getResultSetFromInternalQueries(null, "sp_configure 'user connections'")) {
+                if (!rs1.next()) {
+                    return 0;
+                }
+                return rs1.getInt("maximum");
+            } catch (SQLServerException e1) {
+                return 0;
+            }
         }
-
     }
 
     @Override

src/test/java/com/microsoft/sqlserver/jdbc/TestResource.java

@@ -81,7 +81,6 @@ protected Object[][] getContents() {
             {"R_cannotOpenDatabase", "Cannot open database"}, {"R_shouldNotConnect", "Should not have connected"},
             {"R_loginFailed", "Login failed"}, {"R_exitedMoreSeconds", "Exited in more than {0} seconds."},
             {"R_exitedLessSeconds", "Exited in less than {0} seconds."},
-            {"R_invalidArgumentExecutor", "The argument executor is not valid"},
             {"R_threadInterruptNotSet", "Thread's interrupt status is not set."},
             {"R_connectMirrored", "Connecting to a mirrored"},
             {"R_trustStorePasswordNotSet", "The DataSource trustStore password needs to be set."},

src/test/java/com/microsoft/sqlserver/jdbc/connection/ConnectionDriverTest.java

@@ -35,6 +35,7 @@
 import com.microsoft.sqlserver.jdbc.SQLServerConnectionPoolDataSource;
 import com.microsoft.sqlserver.jdbc.SQLServerDataSource;
 import com.microsoft.sqlserver.jdbc.TestResource;
+import com.microsoft.sqlserver.jdbc.TestUtils;
 import com.microsoft.sqlserver.testframework.AbstractSQLGenerator;
 import com.microsoft.sqlserver.testframework.AbstractTest;
 import com.microsoft.sqlserver.testframework.Constants;
@@ -80,7 +81,8 @@ public void testEncryptedConnection() throws SQLException {
         ds.setEncrypt(true);
         ds.setTrustServerCertificate(true);
         ds.setPacketSize(8192);
-        try (Connection con = ds.getConnection()) {}
+        try (Connection con = ds.getConnection()) {
+        }
     }
 
     @Test
@@ -95,7 +97,8 @@ class MyEventListener implements javax.sql.ConnectionEventListener {
         boolean connClosed = false;
         boolean errorOccurred = false;
 
-        public MyEventListener() {}
+        public MyEventListener() {
+        }
 
         public void connectionClosed(ConnectionEvent event) {
             connClosed = true;
@@ -457,7 +460,7 @@ public void testAbortBadParam() throws SQLException {
             try {
                 conn.abort(null);
             } catch (SQLException e) {
-                assertTrue(e.getMessage().contains(TestResource.getResource("R_invalidArgumentExecutor")));
+                assertTrue(e.getMessage().matches(TestUtils.formatErrorMsg("R_invalidArgument")));
             }
         }
     }
@@ -503,7 +506,8 @@ public void run() {
                 ds.setServerName("invalidServerName" + UUID.randomUUID());
                 ds.setLoginTimeout(5);
 
-                try (Connection con = ds.getConnection()) {} catch (SQLException e) {
+                try (Connection con = ds.getConnection()) {
+                } catch (SQLException e) {
                     isInterrupted = Thread.currentThread().isInterrupted();
                 }
             }

src/test/java/com/microsoft/sqlserver/jdbc/databasemetadata/DatabaseMetaDataTest.java

@@ -422,8 +422,10 @@ public void testGetColumnPrivileges() throws SQLException {
     public void testGetFunctionsWithWrongParams() throws SQLException {
         try (Connection conn = getConnection()) {
             conn.getMetaData().getFunctions("", null, "xp_%");
-            assertTrue(false, TestResource.getResource("R_noSchemaShouldFail"));
-        } catch (Exception ae) {}
+            fail(TestResource.getResource("R_noSchemaShouldFail"));
+        } catch (SQLException e) {
+            assert (e.getMessage().matches(TestUtils.formatErrorMsg("R_invalidArgument")));
+        }
     }
 
     /**
@@ -543,4 +545,21 @@ public void testPreparedStatementMetadataCaching() throws SQLException {
             }
         }
     }
+
+    @Test
+    @Tag(Constants.xAzureSQLDW)
+    public void testGetMaxConnections() throws SQLException {
+        try (Statement stmt = connection.createStatement(); ResultSet rs = stmt
+                .executeQuery("select maximum from sys.configurations where name = 'user connections'")) {
+            assert (null != rs);
+            rs.next();
+
+            DatabaseMetaData databaseMetaData = connection.getMetaData();
+            int maxConn = databaseMetaData.getMaxConnections();
+
+            assertEquals(maxConn, rs.getInt(1));
+        } catch (SQLException e) {
+            fail(e.getMessage());
+        }
+    }
 }