Allow zero and negative values for ConnectionLivenessCheckTimeout

So feature can be easier turned on and off by users. Zero timeout means always
do test-on-borrow, negative timeout means never to test-on-borrow.

Author: lutovich

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

@@ -51,6 +51,6 @@ public long idleTimeBeforeConnectionTest()
 
     public boolean idleTimeBeforeConnectionTestConfigured()
     {
-        return idleTimeBeforeConnectionTest > 0;
+        return idleTimeBeforeConnectionTest >= 0;
     }
 }

driver/src/main/java/org/neo4j/driver/v1/Config.java

@@ -292,22 +292,16 @@ public ConfigBuilder withSessionLivenessCheckTimeout( long timeout )
          * application seeing connection problems, and performance.
          * <p>
          * You normally should not need to tune this parameter.
-         * This feature is turned off by default.
+         * This feature is turned off by default. Value {@code 0} means connections will always be tested for
+         * validity and negative values mean connections will never be tested.
          *
          * @param value the minimum idle time in milliseconds
          * @param unit the unit in which the duration is given
          * @return this builder
          */
         public ConfigBuilder withConnectionLivenessCheckTimeout( long value, TimeUnit unit )
         {
-            long idleTimeBeforeConnectionTestMillis = unit.toMillis( value );
-            if ( idleTimeBeforeConnectionTestMillis <= 0 )
-            {
-                throw new IllegalArgumentException( String.format(
-                        "The timeout value must be positive when converted to ms, but was %d. Given %d %s",
-                        idleTimeBeforeConnectionTestMillis, value, unit ) );
-            }
-            this.idleTimeBeforeConnectionTest = idleTimeBeforeConnectionTestMillis;
+            this.idleTimeBeforeConnectionTest = unit.toMillis( value );
             return this;
         }
 

driver/src/test/java/org/neo4j/driver/internal/ConfigTest.java

@@ -91,35 +91,19 @@ public void shouldSupportLivenessCheckTimeoutSetting() throws Throwable
     }
 
     @Test
-    public void shouldThrowForZeroTimeoutInLivenessCheckTimeoutSetting() throws Throwable
+    public void shouldAllowZeroConnectionLivenessCheckTimeout() throws Throwable
     {
-        Config.ConfigBuilder builder = Config.build();
+        Config config = Config.build().withConnectionLivenessCheckTimeout( 0, TimeUnit.SECONDS ).toConfig();
 
-        try
-        {
-            builder.withConnectionLivenessCheckTimeout( 0, TimeUnit.SECONDS );
-            fail( "Exception expected" );
-        }
-        catch ( Exception e )
-        {
-            assertThat( e, instanceOf( IllegalArgumentException.class ) );
-        }
+        assertEquals( 0, config.idleTimeBeforeConnectionTest() );
     }
 
     @Test
-    public void shouldThrowForNegativeTimeoutInLivenessCheckTimeoutSetting() throws Throwable
+    public void shouldAllowNegativeConnectionLivenessCheckTimeout() throws Throwable
     {
-        Config.ConfigBuilder builder = Config.build();
+        Config config = Config.build().withConnectionLivenessCheckTimeout( -42, TimeUnit.SECONDS ).toConfig();
 
-        try
-        {
-            builder.withConnectionLivenessCheckTimeout( -42, TimeUnit.SECONDS );
-            fail( "Exception expected" );
-        }
-        catch ( Exception e )
-        {
-            assertThat( e, instanceOf( IllegalArgumentException.class ) );
-        }
+        assertEquals( TimeUnit.SECONDS.toMillis( -42 ), config.idleTimeBeforeConnectionTest() );
     }
 
     @Test

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

@@ -39,14 +39,17 @@ public void idleTimeBeforeConnectionTestWhenConfigured()
     @Test
     public void idleTimeBeforeConnectionTestWhenSetToZero()
     {
-        testWithIllegalValue( 0 );
+        PoolSettings settings = new PoolSettings( 10, 0 );
+        assertTrue( settings.idleTimeBeforeConnectionTestConfigured() );
+        assertEquals( 0, settings.idleTimeBeforeConnectionTest() );
     }
 
     @Test
     public void idleTimeBeforeConnectionTestWhenSetToNegativeValue()
     {
         testWithIllegalValue( -1 );
         testWithIllegalValue( -42 );
+        testWithIllegalValue( Integer.MIN_VALUE );
     }
 
     private static void testWithIllegalValue( int value )