From 5726410f6f9fafd04954cf5ee07ac1c5ace9b41b Mon Sep 17 00:00:00 2001
From: Robin Bygrave <robin.bygrave@gmail.com>
Date: Mon, 21 Sep 2015 16:20:14 +1200
Subject: [PATCH] #417 - ENH: Add JSON expressions ... path exists and value at
 path equals value

---
 .../com/avaje/ebean/ExpressionFactory.java    | 40 +++++++++++
 .../java/com/avaje/ebean/ExpressionList.java  | 56 ++++++++++++++-
 .../api/SpiExpressionRequest.java             |  6 ++
 .../server/core/InternalConfiguration.java    | 22 +++++-
 .../server/core/JsonExpressionHandler.java    | 17 +++++
 .../core/NotSupportedJsonExpression.java      | 15 ++++
 .../server/core/OracleJsonExpression.java     | 24 +++++++
 .../server/core/PostgresJsonExpression.java   | 71 ++++++++++++++++++
 .../expression/DefaultExampleExpression.java  |  2 +-
 .../expression/DefaultExpressionFactory.java  | 52 +++++++++++---
 .../server/expression/JsonPathExpression.java | 69 ++++++++++++++++++
 .../server/expression/JunctionExpression.java | 64 +++++++++++++++++
 .../ebeaninternal/server/expression/Op.java   | 62 ++++++++++++++++
 .../server/expression/SimpleExpression.java   | 14 ----
 .../ebeaninternal/server/persist/Binder.java  | 13 +++-
 .../server/query/CQueryPredicates.java        |  6 +-
 .../util/DefaultExpressionList.java           | 72 +++++++++++++++++++
 .../util/DefaultExpressionRequest.java        | 12 +++-
 18 files changed, 584 insertions(+), 33 deletions(-)
 create mode 100644 src/main/java/com/avaje/ebeaninternal/server/core/JsonExpressionHandler.java
 create mode 100644 src/main/java/com/avaje/ebeaninternal/server/core/NotSupportedJsonExpression.java
 create mode 100644 src/main/java/com/avaje/ebeaninternal/server/core/OracleJsonExpression.java
 create mode 100644 src/main/java/com/avaje/ebeaninternal/server/core/PostgresJsonExpression.java
 create mode 100644 src/main/java/com/avaje/ebeaninternal/server/expression/JsonPathExpression.java
 create mode 100644 src/main/java/com/avaje/ebeaninternal/server/expression/Op.java

diff --git a/src/main/java/com/avaje/ebean/ExpressionFactory.java b/src/main/java/com/avaje/ebean/ExpressionFactory.java
index 4d9a5e2fc..72b07e117 100644
--- a/src/main/java/com/avaje/ebean/ExpressionFactory.java
+++ b/src/main/java/com/avaje/ebean/ExpressionFactory.java
@@ -36,6 +36,46 @@ import java.util.Map;
  */
 public interface ExpressionFactory {
 
+  /**
+   * Path exists - for the given path in a JSON document.
+   */
+  Expression jsonExists(String propertyName, String path);
+
+  /**
+   * Path does not exist - for the given path in a JSON document.
+   */
+  Expression jsonNotExists(String propertyName, String path);
+
+  /**
+   * Equal to - for the given path in a JSON document.
+   */
+  Expression jsonEqualTo(String propertyName, String path, Object val);
+
+  /**
+   * Not Equal to - for the given path in a JSON document.
+   */
+  Expression jsonNotEqualTo(String propertyName, String path, Object val);
+
+  /**
+   * Greater than - for the given path in a JSON document.
+   */
+  Expression jsonGreaterThan(String propertyName, String path, Object val);
+
+  /**
+   * Greater than or equal to - for the given path in a JSON document.
+   */
+  Expression jsonGreaterOrEqual(String propertyName, String path, Object val);
+
+  /**
+   * Less than - for the given path in a JSON document.
+   */
+  Expression jsonLessThan(String propertyName, String path, Object val);
+
+  /**
+   * Less than or equal to - for the given path in a JSON document.
+   */
+  Expression jsonLessOrEqualTo(String propertyName, String path, Object val);
+
   /**
    * Equal To - property equal to the given value.
    */
diff --git a/src/main/java/com/avaje/ebean/ExpressionList.java b/src/main/java/com/avaje/ebean/ExpressionList.java
index f546afa84..3f7692bb1 100644
--- a/src/main/java/com/avaje/ebean/ExpressionList.java
+++ b/src/main/java/com/avaje/ebean/ExpressionList.java
@@ -345,12 +345,66 @@ public interface ExpressionList<T> extends Serializable {
    */
   ExpressionList<T> where();
 
+  /**
+   * Path exists - for the given path in a JSON document.
+   *
+   * @param propertyName the property that holds a JSON document
+   * @param path the nested path in the JSON document in dot notation
+   */
+  ExpressionList<T> jsonExists(String propertyName, String path);
+
+  /**
+   * Path does not exist - for the given path in a JSON document.
+   *
+   * @param propertyName the property that holds a JSON document
+   * @param path the nested path in the JSON document in dot notation
+   */
+  ExpressionList<T> jsonNotExists(String propertyName, String path);
+
+  /**
+   * Equal to expression for the value at the given path in the JSON document.
+   *
+   * @param propertyName the property that holds a JSON document
+   * @param path the nested path in the JSON document in dot notation
+   * @param value the value used to test equality against the document path's value
+   */
+  ExpressionList<T> jsonEqualTo(String propertyName, String path, Object value);
+
+  /**
+   * Not Equal to - for the given path in a JSON document.
+   *
+   * @param propertyName the property that holds a JSON document
+   * @param path the nested path in the JSON document in dot notation
+   * @param value the value used to test equality against the document path's value
+   */
+  ExpressionList<T> jsonNotEqualTo(String propertyName, String path, Object value);
+
+  /**
+   * Greater than - for the given path in a JSON document.
+   */
+  ExpressionList<T> jsonGreaterThan(String propertyName, String path, Object val);
+
+  /**
+   * Greater than or equal to - for the given path in a JSON document.
+   */
+  ExpressionList<T> jsonGreaterOrEqual(String propertyName, String path, Object val);
+
+  /**
+   * Less than - for the given path in a JSON document.
+   */
+  ExpressionList<T> jsonLessThan(String propertyName, String path, Object val);
+
+  /**
+   * Less than or equal to - for the given path in a JSON document.
+   */
+  ExpressionList<T> jsonLessOrEqualTo(String propertyName, String path, Object val);
+
   /**
    * Add an Expression to the list.
    * <p>
    * This returns the list so that add() can be chained.
    * </p>
-   * 
+   *
    * <pre>{@code
    *
    * Query<Customer> query = Ebean.find(Customer.class);
diff --git a/src/main/java/com/avaje/ebeaninternal/api/SpiExpressionRequest.java b/src/main/java/com/avaje/ebeaninternal/api/SpiExpressionRequest.java
index 883d6d5ba..3cd185513 100644
--- a/src/main/java/com/avaje/ebeaninternal/api/SpiExpressionRequest.java
+++ b/src/main/java/com/avaje/ebeaninternal/api/SpiExpressionRequest.java
@@ -2,6 +2,7 @@ package com.avaje.ebeaninternal.api;
 
 import java.util.ArrayList;
 
+import com.avaje.ebeaninternal.server.core.JsonExpressionHandler;
 import com.avaje.ebeaninternal.server.core.SpiOrmQueryRequest;
 import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
 
@@ -10,6 +11,11 @@ import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
  */
 public interface SpiExpressionRequest {
 
+  /**
+   * Return the DB specific JSON expression handler.
+   */
+  JsonExpressionHandler getJsonHander();
+
   /**
    * Parse the logical property name to the deployment name.
    */
diff --git a/src/main/java/com/avaje/ebeaninternal/server/core/InternalConfiguration.java b/src/main/java/com/avaje/ebeaninternal/server/core/InternalConfiguration.java
index 8fad1abf6..9d40af426 100644
--- a/src/main/java/com/avaje/ebeaninternal/server/core/InternalConfiguration.java
+++ b/src/main/java/com/avaje/ebeaninternal/server/core/InternalConfiguration.java
@@ -209,11 +209,29 @@ public class InternalConfiguration {
    * For 'As Of' queries return the number of bind variables per predicate.
    */
   private Binder getBinder(TypeManager typeManager, DatabasePlatform databasePlatform) {
+
+    JsonExpressionHandler jsonHandler = getJsonExpressionHandler(databasePlatform);
+
     DbHistorySupport historySupport = databasePlatform.getHistorySupport();
     if (historySupport == null) {
-      return new Binder(typeManager, 0, false);
+      return new Binder(typeManager, 0, false, jsonHandler);
     }
-    return new Binder(typeManager, historySupport.getBindCount(), historySupport.isBindWithFromClause());
+    return new Binder(typeManager, historySupport.getBindCount(), historySupport.isBindWithFromClause(), jsonHandler);
+  }
+
+  /**
+   * Return the JSON expression handler for the given database platform.
+   */
+  private JsonExpressionHandler getJsonExpressionHandler(DatabasePlatform databasePlatform) {
+
+    String name = databasePlatform.getName();
+    if ("postgres".equalsIgnoreCase(name)) {
+      return new PostgresJsonExpression();
+    }
+    if ("oracle".equalsIgnoreCase(name)) {
+      return new OracleJsonExpression();
+    }
+    return new NotSupportedJsonExpression();
   }
 
   /**
diff --git a/src/main/java/com/avaje/ebeaninternal/server/core/JsonExpressionHandler.java b/src/main/java/com/avaje/ebeaninternal/server/core/JsonExpressionHandler.java
new file mode 100644
index 000000000..67ec32bcb
--- /dev/null
+++ b/src/main/java/com/avaje/ebeaninternal/server/core/JsonExpressionHandler.java
@@ -0,0 +1,17 @@
+package com.avaje.ebeaninternal.server.core;
+
+import com.avaje.ebeaninternal.api.SpiExpressionRequest;
+import com.avaje.ebeaninternal.server.expression.Op;
+
+/**
+ * Adds the db platform specific json expression.
+ */
+public interface JsonExpressionHandler {
+
+
+  /**
+   * Write the db platform specific json expression.
+   */
+  void addSql(SpiExpressionRequest request, String propName, String path, Op operator, Object value);
+
+}
diff --git a/src/main/java/com/avaje/ebeaninternal/server/core/NotSupportedJsonExpression.java b/src/main/java/com/avaje/ebeaninternal/server/core/NotSupportedJsonExpression.java
new file mode 100644
index 000000000..840bd237f
--- /dev/null
+++ b/src/main/java/com/avaje/ebeaninternal/server/core/NotSupportedJsonExpression.java
@@ -0,0 +1,15 @@
+package com.avaje.ebeaninternal.server.core;
+
+import com.avaje.ebeaninternal.api.SpiExpressionRequest;
+import com.avaje.ebeaninternal.server.expression.Op;
+
+/**
+ * Not supported JSON expression handler.
+ */
+public class NotSupportedJsonExpression implements JsonExpressionHandler {
+
+  @Override
+  public void addSql(SpiExpressionRequest request, String propName, String path, Op operator, Object value) {
+    throw new RuntimeException("JSON expressions only supported on Postgres and Oracle");
+  }
+}
diff --git a/src/main/java/com/avaje/ebeaninternal/server/core/OracleJsonExpression.java b/src/main/java/com/avaje/ebeaninternal/server/core/OracleJsonExpression.java
new file mode 100644
index 000000000..c4acf95a9
--- /dev/null
+++ b/src/main/java/com/avaje/ebeaninternal/server/core/OracleJsonExpression.java
@@ -0,0 +1,24 @@
+package com.avaje.ebeaninternal.server.core;
+
+import com.avaje.ebeaninternal.api.SpiExpressionRequest;
+import com.avaje.ebeaninternal.server.expression.Op;
+
+/**
+ * Postgres JSON expression handler
+ */
+public class OracleJsonExpression implements JsonExpressionHandler {
+
+  @Override
+  public void addSql(SpiExpressionRequest request, String propName, String path, Op operator, Object value) {
+
+    if (operator == Op.EXISTS) {
+      request.append("json_exists(").append(propName).append(", '$.").append(path).append("')");
+    } else if (operator == Op.NOT_EXISTS) {
+      request.append("not json_exists(").append(propName).append(", '$.").append(path).append("')");
+    } else {
+      request.append("json_value(").append(propName).append(", '$.").append(path).append("')");
+      request.append(operator.bind());
+    }
+
+  }
+}
diff --git a/src/main/java/com/avaje/ebeaninternal/server/core/PostgresJsonExpression.java b/src/main/java/com/avaje/ebeaninternal/server/core/PostgresJsonExpression.java
new file mode 100644
index 000000000..c61f21f0a
--- /dev/null
+++ b/src/main/java/com/avaje/ebeaninternal/server/core/PostgresJsonExpression.java
@@ -0,0 +1,71 @@
+package com.avaje.ebeaninternal.server.core;
+
+import com.avaje.ebeaninternal.api.SpiExpressionRequest;
+import com.avaje.ebeaninternal.server.expression.Op;
+
+/**
+ * Postgres JSON expression handler
+ */
+public class PostgresJsonExpression implements JsonExpressionHandler {
+
+  @Override
+  public void addSql(SpiExpressionRequest request, String propName, String path, Op operator, Object value) {
+
+    StringBuilder sb = new StringBuilder(50);
+    String[] paths = path.split("\\.");
+    if (paths.length == 1) {
+      // (t0.content ->> 'title') = 'Some value'
+      sb.append("(").append(propName).append(" ->> '").append(path).append("')");
+
+    } else {
+      // (t0.content #>> '{path,inner}') = 'Some value'
+      sb.append("(").append(propName).append(" #>> '{");
+      for (int i = 0; i < paths.length; i++) {
+        if (i > 0) {
+          sb.append(",");
+        }
+        sb.append(paths[i]);
+      }
+      sb.append("}')");
+    }
+
+    request.append(castType(sb.toString(), value));
+    request.append(operator.bind());
+  }
+
+  /**
+   * Postgres CAST the type if necessary as text values always returned from the json operators used.
+   */
+  private String castType(String expression, Object value) {
+
+    if (value == null) {
+      // for exists and not-exists expressions
+      return expression;
+    }
+
+    // Postgres cast of returned text value
+    if (isIntegerType(value)) {
+      return expression+"::INTEGER";
+    }
+    if (isNumberType(value)) {
+      return expression+"::DECIMAL";
+    }
+    if (isBooleanType(value)) {
+      return expression+"::BOOLEAN";
+    }
+
+    return expression;
+  }
+
+  private boolean isBooleanType(Object value) {
+    return (value instanceof Boolean);
+  }
+
+  private boolean isIntegerType(Object value) {
+    return (value instanceof Integer) || (value instanceof Long);
+  }
+
+  private boolean isNumberType(Object value) {
+    return (value instanceof Number);
+  }
+}
diff --git a/src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExampleExpression.java b/src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExampleExpression.java
index ee2ffadf7..b357e44da 100644
--- a/src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExampleExpression.java
+++ b/src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExampleExpression.java
@@ -211,7 +211,7 @@ public class DefaultExampleExpression implements SpiExpression, ExampleExpressio
           // exclude the zero values typically to weed out
           // primitive int and long that initialise to 0
           if (includeZeros || !isZero(value)) {
-            list.add(new SimpleExpression(propName, SimpleExpression.Op.EQ, value));
+            list.add(new SimpleExpression(propName, Op.EQ, value));
           }
         }
       }
diff --git a/src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExpressionFactory.java b/src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExpressionFactory.java
index 42f8f7e05..c66eb28df 100644
--- a/src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExpressionFactory.java
+++ b/src/main/java/com/avaje/ebeaninternal/server/expression/DefaultExpressionFactory.java
@@ -1,9 +1,5 @@
 package com.avaje.ebeaninternal.server.expression;
 
-import java.util.Collection;
-import java.util.List;
-import java.util.Map;
-
 import com.avaje.ebean.ExampleExpression;
 import com.avaje.ebean.Expression;
 import com.avaje.ebean.ExpressionFactory;
@@ -15,6 +11,10 @@ import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebeaninternal.api.SpiExpressionFactory;
 import com.avaje.ebeaninternal.api.SpiQuery;
 
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+
 /**
  * Default Expression factory for creating standard expressions.
  */
@@ -36,6 +36,38 @@ public class DefaultExpressionFactory implements SpiExpressionFactory {
     return "sql";
   }
 
+  public Expression jsonExists(String propertyName, String path) {
+    return new JsonPathExpression(propertyName, path, Op.EXISTS, null);
+  }
+
+  public Expression jsonNotExists(String propertyName, String path) {
+    return new JsonPathExpression(propertyName, path, Op.NOT_EXISTS, null);
+  }
+
+  public Expression jsonEqualTo(String propertyName, String path, Object val) {
+    return new JsonPathExpression(propertyName, path, Op.EQ, val);
+  }
+
+  public Expression jsonNotEqualTo(String propertyName, String path, Object val) {
+    return new JsonPathExpression(propertyName, path, Op.NOT_EQ, val);
+  }
+
+  public Expression jsonGreaterThan(String propertyName, String path, Object val) {
+    return new JsonPathExpression(propertyName, path, Op.GT, val);
+  }
+
+  public Expression jsonGreaterOrEqual(String propertyName, String path, Object val) {
+    return new JsonPathExpression(propertyName, path, Op.GT_EQ, val);
+  }
+
+  public Expression jsonLessThan(String propertyName, String path, Object val) {
+    return new JsonPathExpression(propertyName, path, Op.LT, val);
+  }
+
+  public Expression jsonLessOrEqualTo(String propertyName, String path, Object val) {
+    return new JsonPathExpression(propertyName, path, Op.LT_EQ, val);
+  }
+
   /**
    * Equal To - property equal to the given value.
    */
@@ -43,7 +75,7 @@ public class DefaultExpressionFactory implements SpiExpressionFactory {
     if (value == null) {
       return equalsWithNullAsNoop ? NoopExpression.INSTANCE : isNull(propertyName);
     }
-    return new SimpleExpression(propertyName, SimpleExpression.Op.EQ, value);
+    return new SimpleExpression(propertyName, Op.EQ, value);
   }
 
   /**
@@ -53,7 +85,7 @@ public class DefaultExpressionFactory implements SpiExpressionFactory {
     if (value == null) {
       return equalsWithNullAsNoop ? NoopExpression.INSTANCE : isNotNull(propertyName);
     }
-    return new SimpleExpression(propertyName, SimpleExpression.Op.NOT_EQ, value);
+    return new SimpleExpression(propertyName, Op.NOT_EQ, value);
   }
 
   /**
@@ -88,7 +120,7 @@ public class DefaultExpressionFactory implements SpiExpressionFactory {
    */
   public Expression gt(String propertyName, Object value) {
 
-    return new SimpleExpression(propertyName, SimpleExpression.Op.GT, value);
+    return new SimpleExpression(propertyName, Op.GT, value);
   }
 
   /**
@@ -97,7 +129,7 @@ public class DefaultExpressionFactory implements SpiExpressionFactory {
    */
   public Expression ge(String propertyName, Object value) {
 
-    return new SimpleExpression(propertyName, SimpleExpression.Op.GT_EQ, value);
+    return new SimpleExpression(propertyName, Op.GT_EQ, value);
   }
 
   /**
@@ -105,7 +137,7 @@ public class DefaultExpressionFactory implements SpiExpressionFactory {
    */
   public Expression lt(String propertyName, Object value) {
 
-    return new SimpleExpression(propertyName, SimpleExpression.Op.LT, value);
+    return new SimpleExpression(propertyName, Op.LT, value);
   }
 
   /**
@@ -113,7 +145,7 @@ public class DefaultExpressionFactory implements SpiExpressionFactory {
    */
   public Expression le(String propertyName, Object value) {
 
-    return new SimpleExpression(propertyName, SimpleExpression.Op.LT_EQ, value);
+    return new SimpleExpression(propertyName, Op.LT_EQ, value);
   }
 
   /**
diff --git a/src/main/java/com/avaje/ebeaninternal/server/expression/JsonPathExpression.java b/src/main/java/com/avaje/ebeaninternal/server/expression/JsonPathExpression.java
new file mode 100644
index 000000000..5f3244c0b
--- /dev/null
+++ b/src/main/java/com/avaje/ebeaninternal/server/expression/JsonPathExpression.java
@@ -0,0 +1,69 @@
+package com.avaje.ebeaninternal.server.expression;
+
+import com.avaje.ebean.event.BeanQueryRequest;
+import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
+import com.avaje.ebeaninternal.api.SpiExpressionRequest;
+
+/**
+ * Generally speaking tests the value at a given path in the JSON document.
+ * <p>
+ * Supports the usual operators (equal to, greater than etc).
+ * </p>
+ * <p>
+ * The value passed in is expected to be a valid JSON type so string, number, boolean.
+ * </p>
+ */
+class JsonPathExpression extends AbstractExpression {
+
+  /**
+   * The path in the JSON document in dot notation form.
+   */
+  protected final String path;
+
+  /**
+   * The expression operator.
+   */
+  protected final Op operator;
+
+  /**
+   * The bind value used to compare against the document path value.
+   */
+  protected final Object value;
+
+  JsonPathExpression(String propertyName, String path, Op operator, Object value) {
+    super(propertyName);
+    this.path = path;
+    this.operator = operator;
+    this.value = value;
+  }
+
+  @Override
+  public void queryAutoTuneHash(HashQueryPlanBuilder builder) {
+    builder.add(JsonPathExpression.class).add(propName).add(path).add(operator);
+  }
+
+  @Override
+  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
+    queryAutoTuneHash(builder);
+  }
+
+  @Override
+  public int queryBindHash() {
+    return (value == null) ? 0 : value.hashCode();
+  }
+
+  @Override
+  public void addSql(SpiExpressionRequest request) {
+
+    // Use DB specific expression handling (Postgres and Oracle supported)
+    request.getJsonHander().addSql(request, propName, path, operator, value);
+  }
+
+  @Override
+  public void addBindValues(SpiExpressionRequest request) {
+
+    if (value != null) {
+      request.addBindValue(value);
+    }
+  }
+}
diff --git a/src/main/java/com/avaje/ebeaninternal/server/expression/JunctionExpression.java b/src/main/java/com/avaje/ebeaninternal/server/expression/JunctionExpression.java
index d4a6ee80b..71fdae0be 100644
--- a/src/main/java/com/avaje/ebeaninternal/server/expression/JunctionExpression.java
+++ b/src/main/java/com/avaje/ebeaninternal/server/expression/JunctionExpression.java
@@ -313,6 +313,70 @@ abstract class JunctionExpression<T> implements Junction<T>, SpiExpression, Expr
     return exprList.findUnique();
   }
 
+  /**
+   * Path exists - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonExists(String propertyName, String path) {
+    return exprList.jsonExists(propertyName, path);
+  }
+
+  /**
+   * Path does not exist - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonNotExists(String propertyName, String path){
+    return exprList.jsonNotExists(propertyName, path);
+  }
+
+  /**
+   * Equal to - for the value at the given path in the JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonEqualTo(String propertyName, String path, Object value){
+    return exprList.jsonEqualTo(propertyName, path, value);
+  }
+
+  /**
+   * Not Equal to - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonNotEqualTo(String propertyName, String path, Object val){
+    return exprList.jsonNotEqualTo(propertyName, path, val);
+  }
+
+  /**
+   * Greater than - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonGreaterThan(String propertyName, String path, Object val){
+    return exprList.jsonGreaterThan(propertyName, path, val);
+  }
+
+  /**
+   * Greater than or equal to - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonGreaterOrEqual(String propertyName, String path, Object val){
+    return exprList.jsonGreaterOrEqual(propertyName, path, val);
+  }
+
+  /**
+   * Less than - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonLessThan(String propertyName, String path, Object val){
+    return exprList.jsonLessThan(propertyName, path, val);
+  }
+
+  /**
+   * Less than or equal to - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonLessOrEqualTo(String propertyName, String path, Object val){
+    return exprList.jsonLessOrEqualTo(propertyName, path, val);
+  }
+
   @Override
   public ExpressionList<T> ge(String propertyName, Object value) {
     return exprList.ge(propertyName, value);
diff --git a/src/main/java/com/avaje/ebeaninternal/server/expression/Op.java b/src/main/java/com/avaje/ebeaninternal/server/expression/Op.java
new file mode 100644
index 000000000..bb41a1191
--- /dev/null
+++ b/src/main/java/com/avaje/ebeaninternal/server/expression/Op.java
@@ -0,0 +1,62 @@
+package com.avaje.ebeaninternal.server.expression;
+
+/**
+ * Simple operators - equals, greater than, less than etc.
+ */
+public enum Op {
+
+  /**
+   * Exists (JSON).
+   */
+  EXISTS(" is not null "),
+
+  /**
+   * Not Exists (JSON).
+   */
+  NOT_EXISTS(" is null "),
+
+  /**
+   * Equal to
+   */
+  EQ(" = ? "),
+
+  /**
+   * Not equal to.
+   */
+  NOT_EQ(" <> ? "),
+
+  /**
+   *
+   * Less than.
+   */
+
+  LT(" < ? "),
+
+  /**
+   * Less than or equal to.
+   */
+  LT_EQ(" <= ? "),
+
+  /**
+   * Greater than.
+   */
+  GT(" > ? "),
+
+  /**
+   * Greater than or equal to.
+   */
+  GT_EQ(" >= ? ");
+
+  final String exp;
+
+  Op(String exp) {
+    this.exp = exp;
+  }
+
+  /**
+   * Return the bind expression include JDBC ? bind placeholder.
+   */
+  public String bind() {
+    return exp;
+  }
+}
diff --git a/src/main/java/com/avaje/ebeaninternal/server/expression/SimpleExpression.java b/src/main/java/com/avaje/ebeaninternal/server/expression/SimpleExpression.java
index daf90920d..9d2257305 100644
--- a/src/main/java/com/avaje/ebeaninternal/server/expression/SimpleExpression.java
+++ b/src/main/java/com/avaje/ebeaninternal/server/expression/SimpleExpression.java
@@ -10,20 +10,6 @@ public class SimpleExpression extends AbstractExpression {
 
   private static final long serialVersionUID = -382881395755603790L;
 
-  enum Op {
-    EQ(" = ? "), NOT_EQ(" <> ? "), LT(" < ? "), LT_EQ(" <= ? "), GT(" > ? "), GT_EQ(" >= ? ");
-
-    final String exp;
-
-    Op(String exp) {
-      this.exp = exp;
-    }
-
-    public String bind() {
-      return exp;
-    }
-  }
-
   private final Op type;
 
   private final Object value;
diff --git a/src/main/java/com/avaje/ebeaninternal/server/persist/Binder.java b/src/main/java/com/avaje/ebeaninternal/server/persist/Binder.java
index e2aeab3a5..c853ffc00 100644
--- a/src/main/java/com/avaje/ebeaninternal/server/persist/Binder.java
+++ b/src/main/java/com/avaje/ebeaninternal/server/persist/Binder.java
@@ -10,6 +10,7 @@ import java.util.List;
 import javax.persistence.PersistenceException;
 
 import com.avaje.ebeaninternal.api.BindParams;
+import com.avaje.ebeaninternal.server.core.JsonExpressionHandler;
 import com.avaje.ebeaninternal.server.core.Message;
 import com.avaje.ebeaninternal.server.type.DataBind;
 import com.avaje.ebeaninternal.server.type.ScalarType;
@@ -30,13 +31,16 @@ public class Binder {
 
   private final boolean bindAsOfWithFromClause;
 
+  private final JsonExpressionHandler jsonExpressionHandler;
+
   /**
    * Set the PreparedStatement with which to bind variables to.
    */
-  public Binder(TypeManager typeManager, int asOfBindCount, boolean bindAsOfWithFromClause) {
+  public Binder(TypeManager typeManager, int asOfBindCount, boolean bindAsOfWithFromClause, JsonExpressionHandler jsonExpressionHandler) {
     this.typeManager = typeManager;
     this.asOfBindCount = asOfBindCount;
     this.bindAsOfWithFromClause = bindAsOfWithFromClause;
+    this.jsonExpressionHandler = jsonExpressionHandler;
   }
 
   /**
@@ -375,4 +379,11 @@ public class Binder {
         return false;
     }
   }
+
+  /**
+   * Return the JsonExpressionHandler specific to the database.
+   */
+  public JsonExpressionHandler getJsonExpressionHandler() {
+    return jsonExpressionHandler;
+  }
 }
diff --git a/src/main/java/com/avaje/ebeaninternal/server/query/CQueryPredicates.java b/src/main/java/com/avaje/ebeaninternal/server/query/CQueryPredicates.java
index c0dd5851e..236d3ebd2 100644
--- a/src/main/java/com/avaje/ebeaninternal/server/query/CQueryPredicates.java
+++ b/src/main/java/com/avaje/ebeaninternal/server/query/CQueryPredicates.java
@@ -302,7 +302,7 @@ public class CQueryPredicates {
 
     SpiExpressionList<?> whereExp = query.getWhereExpressions();
     if (whereExp != null) {
-      DefaultExpressionRequest whereReq = new DefaultExpressionRequest(request, deployParser);
+      DefaultExpressionRequest whereReq = new DefaultExpressionRequest(request, deployParser, binder);
       whereExprBindValues = whereExp.buildBindValues(whereReq);
       if (buildSql) {
         whereExprSql = whereExp.buildSql(whereReq);
@@ -314,7 +314,7 @@ public class CQueryPredicates {
       OrmQueryProperties chunk = query.getDetail().getChunk(manyProperty.getName(), false);
       SpiExpressionList<?> filterMany = chunk.getFilterMany();
       if (filterMany != null) {
-        DefaultExpressionRequest filterReq = new DefaultExpressionRequest(request, deployParser);
+        DefaultExpressionRequest filterReq = new DefaultExpressionRequest(request, deployParser, binder);
         filterManyExprBindValues = filterMany.buildBindValues(filterReq);
         if (buildSql) {
           filterManyExprSql = filterMany.buildSql(filterReq);
@@ -325,7 +325,7 @@ public class CQueryPredicates {
     // having expression
     SpiExpressionList<?> havingExpr = query.getHavingExpressions();
     if (havingExpr != null) {
-      DefaultExpressionRequest havingReq = new DefaultExpressionRequest(request, deployParser);
+      DefaultExpressionRequest havingReq = new DefaultExpressionRequest(request, deployParser, binder);
       havingExprBindValues = havingExpr.buildBindValues(havingReq);
       if (buildSql) {
         havingExprSql = havingExpr.buildSql(havingReq);
diff --git a/src/main/java/com/avaje/ebeaninternal/util/DefaultExpressionList.java b/src/main/java/com/avaje/ebeaninternal/util/DefaultExpressionList.java
index 1581948db..f59733a0a 100644
--- a/src/main/java/com/avaje/ebeaninternal/util/DefaultExpressionList.java
+++ b/src/main/java/com/avaje/ebeaninternal/util/DefaultExpressionList.java
@@ -363,6 +363,78 @@ public class DefaultExpressionList<T> implements SpiExpressionList<T> {
     return hash;
   }
 
+  /**
+   * Path exists - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonExists(String propertyName, String path) {
+    add(expr.jsonExists(propertyName, path));
+    return this;
+  }
+
+  /**
+   * Path does not exist - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonNotExists(String propertyName, String path){
+    add(expr.jsonNotExists(propertyName, path));
+    return this;
+  }
+  
+  /**
+   * Equal to expression for the value at the given path in the JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonEqualTo(String propertyName, String path, Object value){
+    add(expr.jsonEqualTo(propertyName, path, value));
+    return this;
+  }
+
+  /**
+   * Not Equal to - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonNotEqualTo(String propertyName, String path, Object val){
+    add(expr.jsonNotEqualTo(propertyName, path, val));
+    return this;
+  }
+
+  /**
+   * Greater than - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonGreaterThan(String propertyName, String path, Object val){
+    add(expr.jsonGreaterThan(propertyName, path, val));
+    return this;
+  }
+
+  /**
+   * Greater than or equal to - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonGreaterOrEqual(String propertyName, String path, Object val){
+    add(expr.jsonGreaterOrEqual(propertyName, path, val));
+    return this;
+  }
+
+  /**
+   * Less than - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonLessThan(String propertyName, String path, Object val){
+    add(expr.jsonLessThan(propertyName, path, val));
+    return this;
+  }
+
+  /**
+   * Less than or equal to - for the given path in a JSON document.
+   */
+  @Override
+  public ExpressionList<T> jsonLessOrEqualTo(String propertyName, String path, Object val){
+    add(expr.jsonLessOrEqualTo(propertyName, path, val));
+    return this;
+  }
+
   @Override
   public ExpressionList<T> eq(String propertyName, Object value) {
     add(expr.eq(propertyName, value));
diff --git a/src/main/java/com/avaje/ebeaninternal/util/DefaultExpressionRequest.java b/src/main/java/com/avaje/ebeaninternal/util/DefaultExpressionRequest.java
index 10e469a09..6a62aca31 100644
--- a/src/main/java/com/avaje/ebeaninternal/util/DefaultExpressionRequest.java
+++ b/src/main/java/com/avaje/ebeaninternal/util/DefaultExpressionRequest.java
@@ -3,9 +3,11 @@ package com.avaje.ebeaninternal.util;
 import java.util.ArrayList;
 
 import com.avaje.ebeaninternal.api.SpiExpressionRequest;
+import com.avaje.ebeaninternal.server.core.JsonExpressionHandler;
 import com.avaje.ebeaninternal.server.core.SpiOrmQueryRequest;
 import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
 import com.avaje.ebeaninternal.server.deploy.DeployParser;
+import com.avaje.ebeaninternal.server.persist.Binder;
 
 public class DefaultExpressionRequest implements SpiExpressionRequest {
 
@@ -19,18 +21,26 @@ public class DefaultExpressionRequest implements SpiExpressionRequest {
 
   private final DeployParser deployParser;
 
+  private final Binder binder;
+
   private int paramIndex;
 
-  public DefaultExpressionRequest(SpiOrmQueryRequest<?> queryRequest, DeployParser deployParser) {
+  public DefaultExpressionRequest(SpiOrmQueryRequest<?> queryRequest, DeployParser deployParser, Binder binder) {
     this.queryRequest = queryRequest;
     this.beanDescriptor = queryRequest.getBeanDescriptor();
     this.deployParser = deployParser;
+    this.binder = binder;
   }
 
   public DefaultExpressionRequest(BeanDescriptor<?> beanDescriptor) {
     this.beanDescriptor = beanDescriptor;
     this.queryRequest = null;
     this.deployParser = null;
+    this.binder = null;
+  }
+
+  public JsonExpressionHandler getJsonHander() {
+    return binder.getJsonExpressionHandler();
   }
 
   public String parseDeploy(String logicalProp) {