Removed DriverClosedException

All usages changed back to IllegalStateException. This revert is done because
we should first refine driver errors hierarchy and only then introduce
specific exception types.

Author: lutovich

driver/src/main/java/org/neo4j/driver/internal/InternalDriver.java

@@ -26,7 +26,6 @@
 import org.neo4j.driver.v1.Logger;
 import org.neo4j.driver.v1.Logging;
 import org.neo4j.driver.v1.Session;
-import org.neo4j.driver.v1.exceptions.DriverClosedException;
 
 import static java.lang.String.format;
 
@@ -72,7 +71,7 @@ public final Session session( AccessMode mode )
             // For 1. this closeResources will take no effect as everything is already closed.
             // For 2. this closeResources will close the new connection pool just created to ensure no resource leak.
             closeResources();
-            throw new DriverClosedException();
+            throw driverCloseException();
         }
         return session;
     }
@@ -114,7 +113,12 @@ private void assertOpen()
     {
         if ( closed.get() )
         {
-            throw new DriverClosedException();
+            throw driverCloseException();
         }
     }
+
+    private static RuntimeException driverCloseException()
+    {
+        return new IllegalStateException( "This driver instance has already been closed" );
+    }
 }

driver/src/main/java/org/neo4j/driver/internal/net/pooling/SocketConnectionPool.java

@@ -31,7 +31,6 @@
 import org.neo4j.driver.internal.util.Clock;
 import org.neo4j.driver.internal.util.Supplier;
 import org.neo4j.driver.v1.Logging;
-import org.neo4j.driver.v1.exceptions.DriverClosedException;
 
 /**
  * The pool is designed to buffer certain amount of free sessions into session pool. When closing a session, we first
@@ -180,7 +179,7 @@ private void assertNotClosed()
     {
         if ( closed.get() )
         {
-            throw new DriverClosedException( "Unable to use the connection pool" );
+            throw new IllegalStateException( "Pool closed" );
         }
     }
 

driver/src/main/java/org/neo4j/driver/v1/exceptions/DriverClosedException.java

@@ -42,7 +42,6 @@
 import org.neo4j.driver.internal.util.Clock;
 import org.neo4j.driver.internal.util.FakeClock;
 import org.neo4j.driver.v1.Logging;
-import org.neo4j.driver.v1.exceptions.DriverClosedException;
 
 import static java.util.Collections.newSetFromMap;
 import static org.hamcrest.Matchers.instanceOf;
@@ -268,7 +267,7 @@ public void closeWithConcurrentAcquisitionsEmptiesThePool() throws InterruptedEx
             catch ( Exception e )
             {
                 assertThat( e, instanceOf( ExecutionException.class ) );
-                assertThat( e.getCause(), instanceOf( DriverClosedException.class ) );
+                assertThat( e.getCause(), instanceOf( IllegalStateException.class ) );
             }
         }
         executor.shutdownNow();

driver/src/test/java/org/neo4j/driver/internal/net/pooling/SocketConnectionPoolTest.java

@@ -29,7 +29,6 @@
 import java.util.logging.Level;
 
 import org.neo4j.driver.internal.logging.ConsoleLogging;
-import org.neo4j.driver.v1.exceptions.DriverClosedException;
 import org.neo4j.driver.v1.util.StubServer;
 import org.neo4j.driver.v1.util.TestNeo4j;
 
@@ -59,7 +58,7 @@ public void isEncryptedThrowsForClosedDriver()
             }
             catch ( Exception e )
             {
-                assertThat( e, instanceOf( DriverClosedException.class ) );
+                assertThat( e, instanceOf( IllegalStateException.class ) );
             }
         }
 
@@ -77,7 +76,7 @@ public void sessionThrowsForClosedDriver()
             }
             catch ( Exception e )
             {
-                assertThat( e, instanceOf( DriverClosedException.class ) );
+                assertThat( e, instanceOf( IllegalStateException.class ) );
             }
         }
 
@@ -95,7 +94,7 @@ public void sessionWithModeThrowsForClosedDriver()
             }
             catch ( Exception e )
             {
-                assertThat( e, instanceOf( DriverClosedException.class ) );
+                assertThat( e, instanceOf( IllegalStateException.class ) );
             }
         }
 
@@ -136,7 +135,7 @@ public void useSessionAfterDriverIsClosed()
             }
             catch ( Exception e )
             {
-                assertThat( e, instanceOf( DriverClosedException.class ) );
+                assertThat( e, instanceOf( IllegalStateException.class ) );
             }
         }
     }
@@ -195,7 +194,7 @@ public void useSessionAfterDriverIsClosed() throws Exception
             }
             catch ( Exception e )
             {
-                assertThat( e, instanceOf( DriverClosedException.class ) );
+                assertThat( e, instanceOf( IllegalStateException.class ) );
             }
 
             assertEquals( 0, readServer.exitStatus() );