diff --git a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/properties/LocalOrderProperty.java b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/properties/LocalOrderProperty.java
index d1d0ca9..6b39a8d 100644
--- a/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/properties/LocalOrderProperty.java
+++ b/algebricks/algebricks-core/src/main/java/org/apache/hyracks/algebricks/core/algebra/properties/LocalOrderProperty.java
@@ -84,8 +84,12 @@
 
     @Override
     public boolean equals(Object object) {
-        LocalOrderProperty lop = (LocalOrderProperty) object;
-        return orderColumns.equals(lop.orderColumns);
+        if (object instanceof LocalOrderProperty) {
+            LocalOrderProperty lop = (LocalOrderProperty) object;
+            return orderColumns.equals(lop.orderColumns);
+        } else {
+            return false;
+        }
     }
 
     /**
diff --git a/algebricks/algebricks-rewriter/src/main/java/org/apache/hyracks/algebricks/rewriter/rules/RemoveRedundantVariablesRule.java b/algebricks/algebricks-rewriter/src/main/java/org/apache/hyracks/algebricks/rewriter/rules/RemoveRedundantVariablesRule.java
index 9e867df..eb72db0 100644
--- a/algebricks/algebricks-rewriter/src/main/java/org/apache/hyracks/algebricks/rewriter/rules/RemoveRedundantVariablesRule.java
+++ b/algebricks/algebricks-rewriter/src/main/java/org/apache/hyracks/algebricks/rewriter/rules/RemoveRedundantVariablesRule.java
@@ -100,7 +100,6 @@
             equivalentVarsMap.put(rhs, equivalentVars);
         }
         equivalentVarsMap.put(lhs, equivalentVars);
-        equivalentVars.get(0);
     }
 
     private boolean removeRedundantVariables(Mutable<ILogicalOperator> opRef, IOptimizationContext context)
diff --git a/hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/file/RecordWriter.java b/hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/file/RecordWriter.java
index 1d45b22..2f6b53e 100644
--- a/hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/file/RecordWriter.java
+++ b/hyracks/hyracks-dataflow-std/src/main/java/org/apache/hyracks/dataflow/std/file/RecordWriter.java
@@ -36,7 +36,7 @@
     public RecordWriter(Object[] args) throws Exception {
         OutputStream outputStream = createOutputStream(args);
         if (outputStream != null) {
-            bufferedWriter = new BufferedWriter(new OutputStreamWriter(createOutputStream(args)));
+            bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream));
         } else {
             bufferedWriter = null;
         }
diff --git a/hyracks/hyracks-test-support/src/main/java/org/apache/hyracks/storage/am/rtree/RTreeCheckTuple.java b/hyracks/hyracks-test-support/src/main/java/org/apache/hyracks/storage/am/rtree/RTreeCheckTuple.java
index 160e25c..4f7066f 100644
--- a/hyracks/hyracks-test-support/src/main/java/org/apache/hyracks/storage/am/rtree/RTreeCheckTuple.java
+++ b/hyracks/hyracks-test-support/src/main/java/org/apache/hyracks/storage/am/rtree/RTreeCheckTuple.java
@@ -30,14 +30,18 @@
 
     @Override
     public boolean equals(Object o) {
-        RTreeCheckTuple<T> other = (RTreeCheckTuple<T>) o;
-        for (int i = 0; i < fields.length; i++) {
-            int cmp = fields[i].compareTo(other.getField(i));
-            if (cmp != 0) {
-                return false;
+        if (o instanceof RTreeCheckTuple) {
+            RTreeCheckTuple<T> other = (RTreeCheckTuple<T>) o;
+            for (int i = 0; i < fields.length; i++) {
+                int cmp = fields[i].compareTo(other.getField(i));
+                if (cmp != 0) {
+                    return false;
+                }
             }
+            return true;
+        } else {
+            return false;
         }
-        return true;
     }
 
     public boolean intersect(T o) {