fix: When calling Driver.connect multiple times, System.err is closed…

… unexpectedly. (#2138)

* fix: When calling Driver.connect multiple times, System.err is closed unexpectedly. (#2130)

Use ConsoleHandler instead of StreamHandler when the output stream is
unspecified.

* Refine test cases

pgjdbc/src/main/java/org/postgresql/Driver.java

@@ -36,6 +36,7 @@
 import java.util.Properties;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
+import java.util.logging.ConsoleHandler;
 import java.util.logging.Formatter;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -343,7 +344,7 @@ private void setupLoggerFromProperties(final Properties props) {
       } else if ( DriverManager.getLogStream() != null) {
         handler = new StreamHandler(DriverManager.getLogStream(), formatter);
       } else {
-        handler = new StreamHandler(System.err, formatter);
+        handler = new ConsoleHandler();
       }
     } else {
       handler.setFormatter(formatter);

pgjdbc/src/test/java/org/postgresql/test/jdbc2/DriverTest.java

@@ -21,6 +21,8 @@
 
 import org.junit.Test;
 
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
 import java.io.PrintWriter;
 import java.lang.reflect.Method;
 import java.sql.Connection;
@@ -275,6 +277,40 @@ public void testSetLogStream() throws Exception {
     }
   }
 
+  @Test
+  public void testSystemErrIsNotClosedWhenCreatedMultipleConnections() throws Exception {
+    TestUtil.initDriver();
+    PrintStream err = System.err;
+    String loggerLevel = System.getProperty("loggerLevel");
+    String loggerFile = System.getProperty("loggerFile");
+
+    System.clearProperty("loggerLevel");
+    System.clearProperty("loggerFile");
+    System.setProperty("loggerLevel", "INFO");
+    PrintStream buffer = new PrintStream(new ByteArrayOutputStream());
+    System.setErr(buffer);
+    try {
+      Connection con = DriverManager.getConnection(TestUtil.getURL(), TestUtil.getUser(), TestUtil.getPassword());
+      try {
+        assertNotNull(con);
+      } finally {
+        con.close();
+      }
+      con = DriverManager.getConnection(TestUtil.getURL(), TestUtil.getUser(), TestUtil.getPassword());
+      try {
+        assertNotNull(con);
+        System.err.println();
+        assertFalse("The System.err should not be closed.", System.err.checkError());
+      } finally {
+        con.close();
+      }
+    } finally {
+      System.setProperty("loggerLevel", loggerLevel);
+      System.setProperty("loggerFile", loggerFile);
+      System.setErr(err);
+    }
+  }
+
   private void setProperty(String key, String value) {
     if (value == null) {
       System.clearProperty(key);