Complete code cleanup based on intellij advice.

22 files changed, 118 insertions, 58 deletions

diff --git a/document/src/main/java/com/yahoo/document/select/Context.java b/document/src/main/java/com/yahoo/document/select/Context.java
index a401621b585..481131b4776 100644
--- a/document/src/main/java/com/yahoo/document/select/Context.java
+++ b/document/src/main/java/com/yahoo/document/select/Context.java
@@ -7,7 +7,8 @@ import java.util.HashMap;
 import java.util.Map;
 
 public class Context {
-    private DocumentOperation documentOperation = null;
+    private DocumentOperation documentOperation;
+    private Map<String, Object> variables = new HashMap<>();
 
     public Context(DocumentOperation documentOperation) {
         this.documentOperation = documentOperation;
@@ -28,7 +29,4 @@ public class Context {
     public void setVariables(Map<String, Object> variables) {
         this.variables = variables;
     }
-
-    private Map<String, Object> variables = new HashMap<>();
-
 }
diff --git a/document/src/main/java/com/yahoo/document/select/DocumentSelector.java b/document/src/main/java/com/yahoo/document/select/DocumentSelector.java
index 7f5b92ea233..1ee6ff45c99 100644
--- a/document/src/main/java/com/yahoo/document/select/DocumentSelector.java
+++ b/document/src/main/java/com/yahoo/document/select/DocumentSelector.java
@@ -84,7 +84,7 @@ public class DocumentSelector {
      * @return True if the document is accepted.
      * @throws RuntimeException if the evaluation enters an illegal state
      */
-    public ResultList getMatchingResultList(Context context) {
+    private ResultList getMatchingResultList(Context context) {
         return ResultList.toResultList(expression.evaluate(context));
     }
 
diff --git a/document/src/main/java/com/yahoo/document/select/NowCheckVisitor.java b/document/src/main/java/com/yahoo/document/select/NowCheckVisitor.java
index 5efcdec848a..fd799e36a70 100644
--- a/document/src/main/java/com/yahoo/document/select/NowCheckVisitor.java
+++ b/document/src/main/java/com/yahoo/document/select/NowCheckVisitor.java
@@ -1,8 +1,18 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.document.select;
 
-import com.yahoo.document.select.Visitor;
-import com.yahoo.document.select.rule.*;
+import com.yahoo.document.select.rule.ArithmeticNode;
+import com.yahoo.document.select.rule.AttributeNode;
+import com.yahoo.document.select.rule.ComparisonNode;
+import com.yahoo.document.select.rule.DocumentNode;
+import com.yahoo.document.select.rule.EmbracedNode;
+import com.yahoo.document.select.rule.IdNode;
+import com.yahoo.document.select.rule.LiteralNode;
+import com.yahoo.document.select.rule.LogicNode;
+import com.yahoo.document.select.rule.NegationNode;
+import com.yahoo.document.select.rule.NowNode;
+import com.yahoo.document.select.rule.SearchColumnNode;
+import com.yahoo.document.select.rule.VariableNode;
 
 /**
  * Traverse and check if there exists any now() function in the expression tree.
diff --git a/document/src/main/java/com/yahoo/document/select/Result.java b/document/src/main/java/com/yahoo/document/select/Result.java
index 784b7fdc7e7..5f057da900c 100644
--- a/document/src/main/java/com/yahoo/document/select/Result.java
+++ b/document/src/main/java/com/yahoo/document/select/Result.java
@@ -15,7 +15,7 @@ public enum Result {
     FALSE,
     INVALID;
 
-    // Inherit doc from Object.
+    @Override
     public String toString() {
         return name().toLowerCase();
     }
@@ -38,7 +38,7 @@ public enum Result {
      */
     public static Result toResult(Object value) {
         if (value == null || value == Result.FALSE || value == Boolean.FALSE ||
-            (Number.class.isInstance(value) && ((Number)value).doubleValue() == 0)) {
+            (value instanceof Number && ((Number)value).doubleValue() == 0)) {
             return Result.FALSE;
         } else if (value == INVALID) {
             return Result.INVALID;
diff --git a/document/src/main/java/com/yahoo/document/select/ResultList.java b/document/src/main/java/com/yahoo/document/select/ResultList.java
index 35b4a1ef5be..edf05eb044e 100644
--- a/document/src/main/java/com/yahoo/document/select/ResultList.java
+++ b/document/src/main/java/com/yahoo/document/select/ResultList.java
@@ -43,7 +43,7 @@ public class ResultList {
         }
     }
 
-    List<ResultPair> results = new ArrayList<ResultPair>();
+    private List<ResultPair> results = new ArrayList<>();
 
     public ResultList() {
     }
@@ -86,7 +86,7 @@ public class ResultList {
         }
     }
 
-    boolean combineVariables(FieldPathIteratorHandler.VariableMap output, FieldPathIteratorHandler.VariableMap input) {
+    private boolean combineVariables(FieldPathIteratorHandler.VariableMap output, FieldPathIteratorHandler.VariableMap input) {
         // First, verify that all variables are overlapping
         for (Map.Entry<String, FieldPathIteratorHandler.IndexValue> entry : output.entrySet()) {
             FieldPathIteratorHandler.IndexValue found = input.get(entry.getKey());
@@ -196,7 +196,7 @@ public class ResultList {
             }
             return retVal;
         } else if (value == null || value == Result.FALSE || value == Boolean.FALSE ||
-            (Number.class.isInstance(value) && ((Number)value).doubleValue() == 0)) {
+            (value instanceof Number && ((Number)value).doubleValue() == 0)) {
             return new ResultList(Result.FALSE);
         } else if (value == Result.INVALID) {
             return new ResultList(Result.INVALID);
diff --git a/document/src/main/java/com/yahoo/document/select/convert/NowQueryExpression.java b/document/src/main/java/com/yahoo/document/select/convert/NowQueryExpression.java
index d379a73aec1..a4ce6afb099 100644
--- a/document/src/main/java/com/yahoo/document/select/convert/NowQueryExpression.java
+++ b/document/src/main/java/com/yahoo/document/select/convert/NowQueryExpression.java
@@ -16,7 +16,7 @@ public class NowQueryExpression {
     private final ComparisonNode comparison;
     private final NowQueryNode now;
 
-    public NowQueryExpression(AttributeNode attribute, ComparisonNode comparison, ArithmeticNode arithmetic) {
+    NowQueryExpression(AttributeNode attribute, ComparisonNode comparison, ArithmeticNode arithmetic) {
         this.attribute = attribute;
         this.comparison = comparison;
         this.now = (arithmetic != null ? new NowQueryNode(arithmetic) : new NowQueryNode(0));
diff --git a/document/src/main/java/com/yahoo/document/select/convert/NowQueryNode.java b/document/src/main/java/com/yahoo/document/select/convert/NowQueryNode.java
index 121fa0a45eb..0bd94a3854c 100644
--- a/document/src/main/java/com/yahoo/document/select/convert/NowQueryNode.java
+++ b/document/src/main/java/com/yahoo/document/select/convert/NowQueryNode.java
@@ -10,10 +10,10 @@ import com.yahoo.document.select.rule.ArithmeticNode;
  */
 public class NowQueryNode {
     private final long value;
-    public NowQueryNode(long value) {
+    NowQueryNode(long value) {
         this.value = value;
     }
-    public NowQueryNode(ArithmeticNode node) {
+    NowQueryNode(ArithmeticNode node) {
     	// Assumes that the structure is checked and verified earlier
         this.value = Long.parseLong(node.getItems().get(1).getNode().toString());
     }
diff --git a/document/src/main/java/com/yahoo/document/select/convert/SelectionExpressionConverter.java b/document/src/main/java/com/yahoo/document/select/convert/SelectionExpressionConverter.java
index 46721254b9f..a5708871529 100644
--- a/document/src/main/java/com/yahoo/document/select/convert/SelectionExpressionConverter.java
+++ b/document/src/main/java/com/yahoo/document/select/convert/SelectionExpressionConverter.java
@@ -3,7 +3,20 @@ package com.yahoo.document.select.convert;
 
 import com.yahoo.document.select.NowCheckVisitor;
 import com.yahoo.document.select.Visitor;
-import com.yahoo.document.select.rule.*;
+import com.yahoo.document.select.rule.ArithmeticNode;
+import com.yahoo.document.select.rule.AttributeNode;
+import com.yahoo.document.select.rule.ComparisonNode;
+import com.yahoo.document.select.rule.DocumentNode;
+import com.yahoo.document.select.rule.EmbracedNode;
+import com.yahoo.document.select.rule.ExpressionNode;
+import com.yahoo.document.select.rule.IdNode;
+import com.yahoo.document.select.rule.LiteralNode;
+import com.yahoo.document.select.rule.LogicNode;
+import com.yahoo.document.select.rule.NegationNode;
+import com.yahoo.document.select.rule.NowNode;
+import com.yahoo.document.select.rule.SearchColumnNode;
+import com.yahoo.document.select.rule.VariableNode;
+
 import java.util.HashMap;
 import java.util.Map;
 
@@ -15,14 +28,13 @@ import java.util.Map;
  */
 public class SelectionExpressionConverter implements Visitor {
 
-    private Map<String, NowQueryExpression> expressionMap = new HashMap<String, NowQueryExpression>();
+    private Map<String, NowQueryExpression> expressionMap = new HashMap<>();
 
     private class BuildState {
         public AttributeNode attribute;
         public ComparisonNode comparison;
         public ArithmeticNode arithmetic;
         public NowNode now;
-        public boolean hasNow() { return now != null; }
     }
 
     private BuildState state;
@@ -38,7 +50,7 @@ public class SelectionExpressionConverter implements Visitor {
     }
 
     public Map<String, String> getQueryMap() {
-        Map<String, String> ret = new HashMap<String, String>();
+        Map<String, String> ret = new HashMap<>();
         for (NowQueryExpression expression : expressionMap.values()) {
             ret.put(expression.getDocumentType(), expression.toString());
         }
@@ -92,7 +104,6 @@ public class SelectionExpressionConverter implements Visitor {
         }
         state.comparison = node;
         if (state.attribute != null &&
-            state.comparison != null &&
             (state.arithmetic != null || state.now != null)) {
             NowQueryExpression expression = new NowQueryExpression(state.attribute, state.comparison, state.arithmetic);
             expressionMap.put(expression.getDocumentType(), expression);
diff --git a/document/src/main/java/com/yahoo/document/select/parser/SelectParserUtils.java b/document/src/main/java/com/yahoo/document/select/parser/SelectParserUtils.java
index 6537eefaa7a..2bfed803ea7 100644
--- a/document/src/main/java/com/yahoo/document/select/parser/SelectParserUtils.java
+++ b/document/src/main/java/com/yahoo/document/select/parser/SelectParserUtils.java
@@ -10,7 +10,7 @@ import java.math.BigInteger;
  */
 public class SelectParserUtils {
 
-    public static long decodeLong(String str) {
+    static long decodeLong(String str) {
         if (str.startsWith("0x") || str.startsWith("0X")) {
             str = Long.toString(new BigInteger(str.substring(2), 16).longValue());
         }
diff --git a/document/src/main/java/com/yahoo/document/select/rule/ArithmeticNode.java b/document/src/main/java/com/yahoo/document/select/rule/ArithmeticNode.java
index 015b3f24dd8..c39bd7e668d 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/ArithmeticNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/ArithmeticNode.java
@@ -39,12 +39,12 @@ public class ArithmeticNode implements ExpressionNode {
         return items;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public BucketSet getBucketSet(BucketIdFactory factory) {
         return null;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public Object evaluate(Context context) {
         StringBuilder ret = null;        
         Stack<ValueItem> buf = new Stack<>();
@@ -80,7 +80,7 @@ public class ArithmeticNode implements ExpressionNode {
                     ret.append(val);
                     continue;
                 }
-            } else if (Number.class.isInstance(val)) {
+            } else if (val instanceof Number) {
                 if (!buf.isEmpty()) {
                     while (buf.peek().operator > item.operator) {
                         popOffTheTop(buf);
@@ -174,10 +174,12 @@ public class ArithmeticNode implements ExpressionNode {
         }
     }
 
+    @Override
     public OrderingSpecification getOrdering(int order) {
         return null;
     }
 
+    @Override
     public void accept(Visitor visitor) {
         visitor.visit(this);
     }
@@ -196,7 +198,7 @@ public class ArithmeticNode implements ExpressionNode {
         private int operator;
         private ExpressionNode node;
 
-        public NodeItem(int operator, ExpressionNode node) {
+        NodeItem(int operator, ExpressionNode node) {
             this.operator = operator;
             this.node = node;
         }
diff --git a/document/src/main/java/com/yahoo/document/select/rule/AttributeNode.java b/document/src/main/java/com/yahoo/document/select/rule/AttributeNode.java
index b6d75acd0ea..3e03709d0f1 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/AttributeNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/AttributeNode.java
@@ -2,10 +2,21 @@
 package com.yahoo.document.select.rule;
 
 import com.yahoo.collections.BobHash;
-import com.yahoo.document.*;
+import com.yahoo.document.BucketIdFactory;
+import com.yahoo.document.Document;
+import com.yahoo.document.DocumentGet;
+import com.yahoo.document.DocumentPut;
+import com.yahoo.document.DocumentRemove;
+import com.yahoo.document.DocumentUpdate;
+import com.yahoo.document.FieldPath;
 import com.yahoo.document.datatypes.FieldPathIteratorHandler;
 import com.yahoo.document.datatypes.FieldValue;
-import com.yahoo.document.select.*;
+import com.yahoo.document.select.BucketSet;
+import com.yahoo.document.select.Context;
+import com.yahoo.document.select.OrderingSpecification;
+import com.yahoo.document.select.Result;
+import com.yahoo.document.select.ResultList;
+import com.yahoo.document.select.Visitor;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -16,7 +27,7 @@ import java.util.List;
 public class AttributeNode implements ExpressionNode {
 
     private ExpressionNode value;
-    private final List<Item> items = new ArrayList<Item>();
+    private final List<Item> items = new ArrayList<>();
 
     public AttributeNode(ExpressionNode value, List items) {
         this.value = value;
@@ -43,14 +54,14 @@ public class AttributeNode implements ExpressionNode {
         return items;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public BucketSet getBucketSet(BucketIdFactory factory) {
         return null;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public Object evaluate(Context context) {
-        String pos = value.toString();
+        StringBuilder pos = new StringBuilder(value.toString());
         Object obj = value.evaluate(context);
 
         StringBuilder builder = new StringBuilder();
@@ -74,7 +85,7 @@ public class AttributeNode implements ExpressionNode {
                 obj = evaluateFunction(item.getName(), obj);
             }
 
-            pos = pos + "." + item;
+            pos.append(".").append(item);
         }
 
         if (builder.length() > 0) {
@@ -98,7 +109,7 @@ public class AttributeNode implements ExpressionNode {
 
     private static Object applyFunction(String function, Object value) {
         if (function.equalsIgnoreCase("abs")) {
-            if (Number.class.isInstance(value)) {
+            if (value instanceof Number) {
                 Number nValue = (Number)value;
                 if (value instanceof Double) {
                     return nValue.doubleValue() * (nValue.doubleValue() < 0 ? -1 : 1);
@@ -157,6 +168,7 @@ public class AttributeNode implements ExpressionNode {
         return applyFunction(function, value);
     }
 
+    @Override
     public void accept(Visitor visitor) {
         visitor.visit(this);
     }
@@ -171,6 +183,7 @@ public class AttributeNode implements ExpressionNode {
         return ret.toString();
     }
 
+    @Override
     public OrderingSpecification getOrdering(int order) {
         return null;
     }
diff --git a/document/src/main/java/com/yahoo/document/select/rule/ComparisonNode.java b/document/src/main/java/com/yahoo/document/select/rule/ComparisonNode.java
index 2d4ebc905d6..a7ab3d62c58 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/ComparisonNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/ComparisonNode.java
@@ -108,6 +108,7 @@ public class ComparisonNode implements ExpressionNode {
         return null;
     }
 
+    @Override
     public OrderingSpecification getOrdering(int order) {
         if (lhs instanceof IdNode && rhs instanceof LiteralNode) {
             return getOrdering((IdNode)lhs, (LiteralNode)rhs, operator, order);
@@ -118,7 +119,7 @@ public class ComparisonNode implements ExpressionNode {
         return null;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public BucketSet getBucketSet(BucketIdFactory factory) {
         if (operator.equals("==") || operator.equals("=")) {
             if (lhs instanceof IdNode && rhs instanceof LiteralNode) {
@@ -421,6 +422,7 @@ public class ComparisonNode implements ExpressionNode {
         }
     }
 
+    @Override
     public void accept(Visitor visitor) {
         visitor.visit(this);
     }
diff --git a/document/src/main/java/com/yahoo/document/select/rule/DocumentNode.java b/document/src/main/java/com/yahoo/document/select/rule/DocumentNode.java
index c0907693dab..9b766a56eb3 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/DocumentNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/DocumentNode.java
@@ -1,7 +1,13 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.document.select.rule;
 
-import com.yahoo.document.*;
+import com.yahoo.document.BucketIdFactory;
+import com.yahoo.document.DocumentGet;
+import com.yahoo.document.DocumentOperation;
+import com.yahoo.document.DocumentPut;
+import com.yahoo.document.DocumentRemove;
+import com.yahoo.document.DocumentType;
+import com.yahoo.document.DocumentUpdate;
 import com.yahoo.document.select.BucketSet;
 import com.yahoo.document.select.Context;
 import com.yahoo.document.select.OrderingSpecification;
diff --git a/document/src/main/java/com/yahoo/document/select/rule/EmbracedNode.java b/document/src/main/java/com/yahoo/document/select/rule/EmbracedNode.java
index e1bd4b2d53f..7bf3413bafb 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/EmbracedNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/EmbracedNode.java
@@ -27,11 +27,12 @@ public class EmbracedNode implements ExpressionNode {
         return this;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public BucketSet getBucketSet(BucketIdFactory factory) {
         return node.getBucketSet(factory);
     }
 
+    @Override
     public Object evaluate(Context context) {
         return node.evaluate(context);
     }
@@ -41,10 +42,12 @@ public class EmbracedNode implements ExpressionNode {
         return "(" + node + ")";
     }
 
+    @Override
     public void accept(Visitor visitor) {
         visitor.visit(this);
     }
 
+    @Override
     public OrderingSpecification getOrdering(int order) {
         return null;
     }
diff --git a/document/src/main/java/com/yahoo/document/select/rule/ExpressionNode.java b/document/src/main/java/com/yahoo/document/select/rule/ExpressionNode.java
index 29f49c4459c..9350b8ac1c5 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/ExpressionNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/ExpressionNode.java
@@ -21,14 +21,14 @@ public interface ExpressionNode {
      * @param doc The document to evaluate over.
      * @return The value of this.
      */
-    public Object evaluate(Context doc);
+    Object evaluate(Context doc);
 
     /**
      * Returns the set of bucket ids covered by this node.
      *
      * @param factory The factory used by the current application.
      */
-    public BucketSet getBucketSet(BucketIdFactory factory);
+    BucketSet getBucketSet(BucketIdFactory factory);
 
     /**
      * If this document selection implies a specific ordering (using the orderdoc scheme),
@@ -36,13 +36,13 @@ public interface ExpressionNode {
      *
      * @param order The order in which we are looking to traverse the ordering (ASCENDING or DESCENDING)
      */
-    public OrderingSpecification getOrdering(int order);
+    OrderingSpecification getOrdering(int order);
 
     /**
      * Perform visitation of this node.
      *
      * @param visitor The visitor that wishes to visit the node.
      */
-    public void accept(Visitor visitor);
+    void accept(Visitor visitor);
 
 }
diff --git a/document/src/main/java/com/yahoo/document/select/rule/IdNode.java b/document/src/main/java/com/yahoo/document/select/rule/IdNode.java
index 3c15a2866cc..3ca53c1d07d 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/IdNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/IdNode.java
@@ -3,8 +3,11 @@ package com.yahoo.document.select.rule;
 
 import com.yahoo.document.DocumentId;
 import com.yahoo.document.BucketIdFactory;
-import com.yahoo.document.select.*;
-import com.yahoo.document.idstring.*;
+import com.yahoo.document.idstring.OrderDocIdString;
+import com.yahoo.document.select.BucketSet;
+import com.yahoo.document.select.Context;
+import com.yahoo.document.select.OrderingSpecification;
+import com.yahoo.document.select.Visitor;
 
 /**
  * @author Simon Thoresen Hult
@@ -46,7 +49,7 @@ public class IdNode implements ExpressionNode {
         return divisionBits;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public BucketSet getBucketSet(BucketIdFactory factory) {
         return null;
     }
@@ -55,7 +58,7 @@ public class IdNode implements ExpressionNode {
         return null;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public Object evaluate(Context context) {
         DocumentId id = context.getDocumentOperation().getId();
         if (id == null) {
@@ -97,6 +100,7 @@ public class IdNode implements ExpressionNode {
         return null;
     }
 
+    @Override
     public void accept(Visitor visitor) {
         visitor.visit(this);
     }
diff --git a/document/src/main/java/com/yahoo/document/select/rule/LogicNode.java b/document/src/main/java/com/yahoo/document/select/rule/LogicNode.java
index 804dda5741d..1ae397398b3 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/LogicNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/LogicNode.java
@@ -188,11 +188,11 @@ public class LogicNode implements ExpressionNode {
         buf.push(new LazyCombinedItem(lhs, rhs));
     }
 
+    @Override
     public void accept(Visitor visitor) {
         visitor.visit(this);
     }
 
-    // Inherit doc from Object.
     @Override
     public String toString() {
         StringBuilder ret = new StringBuilder();
diff --git a/document/src/main/java/com/yahoo/document/select/rule/NegationNode.java b/document/src/main/java/com/yahoo/document/select/rule/NegationNode.java
index c89759bbf07..ba75b13747d 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/NegationNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/NegationNode.java
@@ -28,16 +28,17 @@ public class NegationNode implements ExpressionNode {
         return this;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public BucketSet getBucketSet(BucketIdFactory factory) {
         return null;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public Object evaluate(Context context) {
         return Result.invert(Result.toResult(node.evaluate(context)));
     }
 
+    @Override
     public void accept(Visitor visitor) {
         visitor.visit(this);
     }
@@ -47,6 +48,7 @@ public class NegationNode implements ExpressionNode {
         return "not " + node;
     }
 
+    @Override
     public OrderingSpecification getOrdering(int order) {
         return null;
     }
diff --git a/document/src/main/java/com/yahoo/document/select/rule/NowNode.java b/document/src/main/java/com/yahoo/document/select/rule/NowNode.java
index 900423addff..567d9ddcb1f 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/NowNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/NowNode.java
@@ -1,22 +1,25 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.document.select.rule;
+
 import com.yahoo.document.BucketIdFactory;
-import com.yahoo.document.select.*;
+import com.yahoo.document.select.BucketSet;
+import com.yahoo.document.select.Context;
+import com.yahoo.document.select.OrderingSpecification;
+import com.yahoo.document.select.Visitor;
 
 /**
  * @author Ulf Lilleengen
  */
 public class NowNode implements ExpressionNode {
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public BucketSet getBucketSet(BucketIdFactory factory) {
         return null;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public Object evaluate(Context context) {
-        Object ret = System.currentTimeMillis() / 1000;  
-        return ret;
+        return System.currentTimeMillis() / 1000;
     }
 
     @Override
@@ -24,10 +27,11 @@ public class NowNode implements ExpressionNode {
         return "now()";
     }
 
+    @Override
     public OrderingSpecification getOrdering(int order) {
         return null;
     }
-
+    @Override
     public void accept(Visitor visitor) {
         visitor.visit(this);
     }
diff --git a/document/src/main/java/com/yahoo/document/select/rule/SearchColumnNode.java b/document/src/main/java/com/yahoo/document/select/rule/SearchColumnNode.java
index ffcf576dcfc..071e51c192f 100644
--- a/document/src/main/java/com/yahoo/document/select/rule/SearchColumnNode.java
+++ b/document/src/main/java/com/yahoo/document/select/rule/SearchColumnNode.java
@@ -3,7 +3,10 @@ package com.yahoo.document.select.rule;
 
 import com.yahoo.document.BucketDistribution;
 import com.yahoo.document.BucketIdFactory;
-import com.yahoo.document.select.*;
+import com.yahoo.document.select.BucketSet;
+import com.yahoo.document.select.Context;
+import com.yahoo.document.select.OrderingSpecification;
+import com.yahoo.document.select.Visitor;
 
 /**
  * @author Simon Thoresen Hult
@@ -31,16 +34,17 @@ public class SearchColumnNode implements ExpressionNode {
         return distribution;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public BucketSet getBucketSet(BucketIdFactory factory) {
         return null;
     }
 
-    // Inherit doc from ExpressionNode.
+    @Override
     public Object evaluate(Context context) {
         return distribution.getColumn(factory.getBucketId(context.getDocumentOperation().getId()));
     }
 
+    @Override
     public void accept(Visitor visitor) {
         visitor.visit(this);
     }
@@ -50,6 +54,7 @@ public class SearchColumnNode implements ExpressionNode {
         return "searchcolumn." + field;
     }
 
+    @Override
     public OrderingSpecification getOrdering(int order) {
         return null;
     }
diff --git a/document/src/main/java/com/yahoo/document/select/simple/IdSpecParser.java b/document/src/main/java/com/yahoo/document/select/simple/IdSpecParser.java
index f792c4b8c0f..db4d46e871b 100644
--- a/document/src/main/java/com/yahoo/document/select/simple/IdSpecParser.java
+++ b/document/src/main/java/com/yahoo/document/select/simple/IdSpecParser.java
@@ -9,7 +9,7 @@ import com.yahoo.document.select.rule.IdNode;
 public class IdSpecParser extends Parser {
     private IdNode id;
     public IdNode getId() { return id; }
-    public boolean isUserSpec() { return "user".equals(id.getField()); }
+    boolean isUserSpec() { return "user".equals(id.getField()); }
     public boolean parse(CharSequence s) {
         boolean retval = false;
         int pos = eatWhite(s);
diff --git a/document/src/main/java/com/yahoo/document/select/simple/StringParser.java b/document/src/main/java/com/yahoo/document/select/simple/StringParser.java
index d43c57aee03..50d4915e360 100644
--- a/document/src/main/java/com/yahoo/document/select/simple/StringParser.java
+++ b/document/src/main/java/com/yahoo/document/select/simple/StringParser.java
@@ -14,7 +14,7 @@ public class StringParser extends Parser {
         int pos = eatWhite(s);
         if (pos + 1 < s.length()) {
         if (s.charAt(pos++) == '"') {
-            StringBuffer str = new StringBuffer("");
+            StringBuilder str = new StringBuilder();
             for(; (pos < s.length()) && (s.charAt(pos) != '"');pos++) {
                 if ((pos < s.length()) && (s.charAt(pos) == '\\')) {
                     pos++;