Parameters can't be nodes, relationships or paths

Driver should not accept nodes, relationships nor paths to be sent over the
wire.

Author: pontusmelke

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

@@ -43,8 +43,7 @@
 public abstract class Values
 {
     public static final Value EmptyMap = value( Collections.emptyMap() );
-
-    public static Value NULL = NullValue.NULL;
+    public static final Value NULL = NullValue.NULL;
 
     private Values()
     {
@@ -271,7 +270,9 @@ public static Map<String,Value> parameters( Object... keysAndValues )
         HashMap<String,Value> map = new HashMap<>( keysAndValues.length / 2 );
         for ( int i = 0; i < keysAndValues.length; i += 2 )
         {
-            map.put( keysAndValues[i].toString(), value( keysAndValues[i + 1] ) );
+            Object value = keysAndValues[i + 1];
+            assertParameter( value );
+            map.put( keysAndValues[i].toString(), value( value ) );
         }
         return map;
     }
@@ -491,4 +492,21 @@ public Path apply( Value val )
             return val.asPath();
         }
     };
+
+    private static void assertParameter( Object value )
+    {
+        if ( value instanceof Node )
+        {
+            throw new ClientException( "Nodes can't be used as parameters." );
+        }
+        if ( value instanceof Relationship )
+        {
+            throw new ClientException( "Relationships can't be used as parameters." );
+        }
+        if ( value instanceof Path )
+        {
+            throw new ClientException( "Paths can't be used as parameters." );
+        }
+
+    }
 }

driver/src/test/java/org/neo4j/driver/v1/integration/ParametersIT.java

@@ -22,15 +22,17 @@
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
 
+import org.neo4j.driver.v1.Node;
+import org.neo4j.driver.v1.Path;
 import org.neo4j.driver.v1.Record;
+import org.neo4j.driver.v1.Relationship;
 import org.neo4j.driver.v1.ResultCursor;
 import org.neo4j.driver.v1.Value;
 import org.neo4j.driver.v1.exceptions.ClientException;
 import org.neo4j.driver.v1.util.TestNeo4jSession;
 
 import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.MatcherAssert.assertThat;
-
 import static org.neo4j.driver.v1.Values.parameters;
 
 public class ParametersIT
@@ -387,4 +389,52 @@ public void settingInvalidParameterTypeShouldThrowHelpfulError() throws Throwabl
         // When
         session.run( "anything", parameters( "k", new Object() ) );
     }
+
+    @Test
+    public void shouldNotBePossibleToUseNodeAsParameter()
+    {
+        // GIVEN
+        ResultCursor cursor = session.run( "CREATE (a:Node) RETURN a" );
+        cursor.first();
+        Node node = cursor.value( 0 ).asNode();
+
+        //Expect
+        exception.expect( ClientException.class );
+        exception.expectMessage( "Nodes can't be used as parameters" );
+
+        // WHEN
+        session.run( "RETURN {a}", parameters( "a", node ) );
+    }
+
+    @Test
+    public void shouldNotBePossibleToUseRelationshipAsParameter()
+    {
+        // GIVEN
+        ResultCursor cursor = session.run( "CREATE (a:Node), (b:Node), (a)-[r:R]->(b) RETURN r" );
+        cursor.first();
+        Relationship relationship = cursor.value( 0 ).asRelationship();
+
+        //Expect
+        exception.expect( ClientException.class );
+        exception.expectMessage( "Relationships can't be used as parameters" );
+
+        // WHEN
+        session.run( "RETURN {a}", parameters( "a", relationship ) );
+    }
+
+    @Test
+    public void shouldNotBePossibleToUsePathAsParameter()
+    {
+        // GIVEN
+        ResultCursor cursor = session.run( "CREATE (a:Node), (b:Node), p=(a)-[r:R]->(b) RETURN p" );
+        cursor.first();
+        Path path = cursor.value( 0 ).asPath();
+
+        //Expect
+        exception.expect( ClientException.class );
+        exception.expectMessage( "Paths can't be used as parameters" );
+
+        // WHEN
+        session.run( "RETURN {a}", parameters( "a", path ) );
+    }
 }

driver/src/test/java/org/neo4j/driver/v1/util/Neo4jInstaller.java

@@ -101,7 +101,8 @@ public int runCommand( String... cmd ) throws IOException
                 // Neo4j, however, works with a specific version of Java. This allows
                 // specifying which Java version to use for Neo4j separately from which
                 // version to use for the driver tests.
-                env.containsKey( "NEO4J_JAVA" ) ? env.get( "NEO4J_JAVA" ) : env.get( "JAVA_HOME" ) );
+                env.containsKey( "NEO4J_JAVA" ) ? env.get( "NEO4J_JAVA" ) :
+                System.getProperties().getProperty( "java.home" ) );
         Process process = pb.command( cmd ).start();
         while (true)
         {