Fix Issue #2928 number of ports not equal to number of servers in dat…

…asource (#2929)

* In BaseDataSource, check to make sure the number of servers is equal to the number of ports.
Throw an IllegalArgumentException if they are not.
Added test case to ensure

* changed test to remove nesting
Add the ports and server names to the error message

pgjdbc/src/main/java/org/postgresql/ds/common/BaseDataSource.java

@@ -1337,8 +1337,16 @@ public String getUrl() {
         url.append(",");
       }
       url.append(serverNames[i]);
-      if (portNumbers != null && portNumbers.length >= i && portNumbers[i] != 0) {
-        url.append(":").append(portNumbers[i]);
+      if (portNumbers != null) {
+        if (serverNames.length != portNumbers.length) {
+          throw new IllegalArgumentException(
+              String.format("Invalid argument: number of port %s entries must equal number of serverNames %s",
+                  Arrays.toString(portNumbers), Arrays.toString(serverNames)));
+        }
+        if (portNumbers.length >= i && portNumbers[i] != 0) {
+          url.append(":").append(portNumbers[i]);
+        }
+
       }
     }
     url.append("/");

pgjdbc/src/test/java/org/postgresql/test/jdbc2/optional/BaseDataSourceFailoverUrlsTest.java

@@ -6,6 +6,7 @@
 package org.postgresql.test.jdbc2.optional;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThrows;
 
 import org.postgresql.ds.common.BaseDataSource;
 
@@ -67,6 +68,16 @@ public void testEmptyPorts() {
     assertEquals(0, bds.getPortNumbers()[0]);
   }
 
+  @Test
+  public void testWrongNumberOfPorts() {
+    BaseDataSource bds = newDS();
+    bds.setDatabaseName("database");
+    bds.setServerNames(new String[] {"localhost", "localhost1"});
+    bds.setPortNumbers(new int[] {6432});
+    assertThrows("Number of ports not equal to the number of servers should throw an exception",
+        IllegalArgumentException.class, () -> bds.getUrl());
+  }
+
   private BaseDataSource newDS() {
     return new BaseDataSource() {
       @Override