diff --git a/querydsl-core/pom.xml b/querydsl-core/pom.xml
index 3f9354f4e..53879cca4 100644
--- a/querydsl-core/pom.xml
+++ b/querydsl-core/pom.xml
@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="UTF-8"?>
+<?xml version="1.0" encoding="UTF-8"?>
 <project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd" xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
   <modelVersion>4.0.0</modelVersion>
 
@@ -72,7 +72,7 @@
       <artifactId>jdepend</artifactId>
       <version>2.9.1</version>
       <scope>test</scope>
-    </dependency>    
+    </dependency>
   </dependencies>
   
   <build>
@@ -141,4 +141,4 @@
   <properties>
     <bridge-method.version>1.13</bridge-method.version>
   </properties>
-</project>
+</project>
diff --git a/querydsl-core/src/main/java/com/querydsl/core/types/FactoryExpressionBase.java b/querydsl-core/src/main/java/com/querydsl/core/types/FactoryExpressionBase.java
index 63cd9da6a..487962041 100644
--- a/querydsl-core/src/main/java/com/querydsl/core/types/FactoryExpressionBase.java
+++ b/querydsl-core/src/main/java/com/querydsl/core/types/FactoryExpressionBase.java
@@ -82,4 +82,16 @@ public abstract class FactoryExpressionBase<T> extends ExpressionBase<T> impleme
         return new FactoryExpressionWrapper<T>(this);
     }
 
+    @Override
+    public boolean equals(Object o) {
+        if (o == this) {
+            return true;
+        } else if (o instanceof FactoryExpression) {
+            return getClass().equals(o.getClass())
+                    && getArgs().equals(((FactoryExpression) o).getArgs());
+        } else {
+            return false;
+        }
+    }
+
 }
diff --git a/querydsl-core/src/main/java/com/querydsl/core/types/dsl/PathBuilderValidator.java b/querydsl-core/src/main/java/com/querydsl/core/types/dsl/PathBuilderValidator.java
index d6ad88166..453e5ea01 100644
--- a/querydsl-core/src/main/java/com/querydsl/core/types/dsl/PathBuilderValidator.java
+++ b/querydsl-core/src/main/java/com/querydsl/core/types/dsl/PathBuilderValidator.java
@@ -13,6 +13,7 @@
  */
 package com.querydsl.core.types.dsl;
 
+import java.io.Serializable;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.util.Collection;
@@ -25,7 +26,7 @@ import com.querydsl.core.util.ReflectionUtils;
 /**
  * {@code PathBuilderValidator} validates {@link PathBuilder} properties at creation time
  */
-public interface PathBuilderValidator {
+public interface PathBuilderValidator extends Serializable {
 
     /**
      * Validates the given property of given class
diff --git a/querydsl-core/src/test/java/com/querydsl/core/types/Concatenation.java b/querydsl-core/src/test/java/com/querydsl/core/types/Concatenation.java
index 55b784bd0..d3b1dcb64 100644
--- a/querydsl-core/src/test/java/com/querydsl/core/types/Concatenation.java
+++ b/querydsl-core/src/test/java/com/querydsl/core/types/Concatenation.java
@@ -20,7 +20,7 @@ import java.util.List;
  * @author tiwe
  *
  */
-public class Concatenation extends ExpressionBase<String> implements FactoryExpression<String> {
+public class Concatenation extends FactoryExpressionBase<String> {
 
     private static final long serialVersionUID = -355693583588722395L;
 
diff --git a/querydsl-core/src/test/java/com/querydsl/core/types/SerializationTest.java b/querydsl-core/src/test/java/com/querydsl/core/types/SerializationTest.java
index 4cac2958d..8198bb845 100644
--- a/querydsl-core/src/test/java/com/querydsl/core/types/SerializationTest.java
+++ b/querydsl-core/src/test/java/com/querydsl/core/types/SerializationTest.java
@@ -3,15 +3,79 @@ package com.querydsl.core.types;
 import static com.querydsl.core.testutil.Serialization.serialize;
 import static org.junit.Assert.assertEquals;
 
-import org.junit.Test;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Modifier;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
 
-import com.querydsl.core.types.dsl.Expressions;
-import com.querydsl.core.types.dsl.SimplePath;
+import org.junit.Test;
+import org.reflections.Reflections;
+
+import com.google.common.collect.Maps;
+import com.querydsl.core.DefaultQueryMetadata;
+import com.querydsl.core.QueryMetadata;
+import com.querydsl.core.group.GroupBy;
+import com.querydsl.core.group.GroupExpression;
+import com.querydsl.core.testutil.Serialization;
+import com.querydsl.core.types.dsl.*;
 
 public class SerializationTest {
 
+    public enum Gender { MALE, FEMALE }
+
     @Test
-    public void roundtrip() throws Exception {
+    public void Expressions() throws Exception {
+        Map<Class<?>, Object> args = Maps.newHashMap();
+        args.put(Object.class, "obj");
+        args.put(BeanPath.class, new EntityPathBase<Object>(Object.class, "obj"));
+        args.put(Class.class, Integer.class);
+        args.put(Class[].class, new Class[]{Object.class, Object.class});
+        args.put(java.util.Date.class, new java.util.Date(0));
+        args.put(java.sql.Date.class, new java.sql.Date(0));
+        args.put(java.sql.Time.class, new java.sql.Time(0));
+        args.put(java.sql.Timestamp.class, new java.sql.Timestamp(0));
+        args.put(Expression.class, Expressions.enumPath(Gender.class, "e"));
+        args.put(Expression[].class, new Expression<?>[]{
+                Expressions.enumPath(Gender.class, "e"), Expressions.stringPath("s")});
+        args.put(FactoryExpression.class, Projections.tuple(Expressions.stringPath("str")));
+        args.put(GroupExpression.class, GroupBy.avg(Expressions.numberPath(Integer.class, "num")));
+        args.put(Number.class, 1);
+        args.put(Operator.class, Ops.AND);
+        args.put(Path.class, Expressions.stringPath("str"));
+        args.put(PathBuilderValidator.class, PathBuilderValidator.DEFAULT);
+        args.put(PathMetadata.class, PathMetadataFactory.forVariable("obj"));
+        args.put(PathInits.class, PathInits.DEFAULT);
+        args.put(Predicate.class, Expressions.path(Object.class, "obj").isNull());
+        args.put(QueryMetadata.class, new DefaultQueryMetadata());
+        args.put(String.class, "obj");
+
+        Reflections reflections = new Reflections();
+        Set<Class<? extends Expression>> types = reflections.getSubTypesOf(Expression.class);
+        for (Class<?> type : types) {
+            if (!type.isInterface() && !type.isMemberClass() && !Modifier.isAbstract(type.getModifiers())) {
+                for (Constructor<?> c : type.getConstructors()) {
+                    Object[] parameters = new Object[c.getParameterTypes().length];
+                    for (int i = 0; i < c.getParameterTypes().length; i++) {
+                        parameters[i] = Objects.requireNonNull(args.get(c.getParameterTypes()[i]),
+                                c.getParameterTypes()[i].getName());
+                    }
+                    c.setAccessible(true);
+                    Object o = c.newInstance(parameters);
+                    assertEquals(o, Serialization.serialize(o));
+                }
+            }
+        }
+    }
+
+    @Test
+    public void Order() {
+        OrderSpecifier<?> order = new OrderSpecifier<String>(Order.ASC, Expressions.stringPath("str"));
+        assertEquals(order, Serialization.serialize(order));
+    }
+
+    @Test
+    public void Roundtrip() throws Exception {
         Path<?> path = ExpressionUtils.path(Object.class, "entity");
         SimplePath<?> path2 = Expressions.path(Object.class, "entity");
         assertEquals(path, serialize(path));