Revert "ATLAS-1369 - Java 7 Support"

repository/src/main/java/org/apache/atlas/gremlin/optimizer/ExpressionFinder.java

@@ -17,7 +17,7 @@
  */
 package org.apache.atlas.gremlin.optimizer;
 
-import com.google.common.base.Function;
+import java.util.function.Function;
 
 import org.apache.atlas.groovy.AbstractFunctionExpression;
 import org.apache.atlas.groovy.GroovyExpression;

repository/src/main/java/org/apache/atlas/gremlin/optimizer/HasForbiddenType.java

@@ -19,13 +19,12 @@ package org.apache.atlas.gremlin.optimizer;
 
 import java.util.HashSet;
 import java.util.Set;
+import java.util.function.Function;
 
 import org.apache.atlas.gremlin.GremlinExpressionFactory;
 import org.apache.atlas.groovy.GroovyExpression;
 import org.apache.atlas.groovy.TraversalStepType;
 
-import com.google.common.base.Function;
-
 /**
  * Function that tests whether the expression is an 'or'
  * graph traversal function.

repository/src/main/java/org/apache/atlas/gremlin/optimizer/IsOr.java

@@ -17,7 +17,7 @@
  */
 package org.apache.atlas.gremlin.optimizer;
 
-import com.google.common.base.Function;
+import java.util.function.Function;
 
 import org.apache.atlas.groovy.FunctionCallExpression;
 import org.apache.atlas.groovy.GroovyExpression;

repository/src/main/java/org/apache/atlas/gremlin/optimizer/IsOrParent.java

@@ -17,7 +17,7 @@
  */
 package org.apache.atlas.gremlin.optimizer;
 
-import com.google.common.base.Function;
+import java.util.function.Function;
 
 import org.apache.atlas.groovy.AbstractFunctionExpression;
 import org.apache.atlas.groovy.FunctionCallExpression;