Adding support for Set user type as json column.

Author: amjedonline

src/main/java/com/marvinformatics/hibernate/json/JsonSetUserType.java

@@ -0,0 +1,78 @@
+/**
+ * Copyright (C) 2016 Marvin Herman Froeder ([email protected])
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.marvinformatics.hibernate.json;
+
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Set;
+import com.fasterxml.jackson.databind.JavaType;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.hibernate.HibernateException;
+import org.hibernate.collection.internal.PersistentSet;
+import org.hibernate.collection.spi.PersistentCollection;
+import org.hibernate.engine.spi.SessionImplementor;
+import org.hibernate.persister.collection.CollectionPersister;
+import org.hibernate.usertype.UserCollectionType;
+
+public class JsonSetUserType extends JsonUserType implements UserCollectionType {
+    public JsonSetUserType() {
+    }
+
+    public JavaType createJavaType(ObjectMapper mapper) {
+        return mapper.getTypeFactory().constructCollectionType(Set.class, this.returnedClass());
+    }
+
+    public PersistentCollection instantiate(SessionImplementor session, CollectionPersister persister) throws HibernateException {
+        return new PersistentSet(session);
+    }
+
+    private PersistentSet cast(Object collection) {
+        return (PersistentSet) collection;
+    }
+
+    public PersistentCollection wrap(SessionImplementor session, Object collection) {
+        return new PersistentSet(session, (Set<?>) collection);
+    }
+
+    public Iterator<?> getElementsIterator(Object collection) {
+        return this.cast(collection).iterator();
+    }
+
+    public boolean contains(Object collection, Object entity) {
+        return this.cast(collection).contains(entity);
+    }
+
+    public Object indexOf(Object collection, Object entity) {
+        throw new UnsupportedOperationException();
+    }
+
+    public Object replaceElements(Object original,
+            Object target,
+            CollectionPersister persister,
+            Object owner,
+            Map copyCache,
+            SessionImplementor session) throws HibernateException {
+        PersistentSet originalSet = this.cast(original);
+        PersistentSet targetSet = this.cast(target);
+        targetSet.clear();
+        targetSet.addAll(originalSet);
+        return target;
+    }
+
+    public Object instantiate(int anticipatedSize) {
+        return new PersistentSet();
+    }
+}

src/test/java/com/marvinformatics/hibernate/json/JsonSetUserTypeTest.java

@@ -0,0 +1,93 @@
+/**
+ * Copyright (C) 2016 Marvin Herman Froeder ([email protected])
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.marvinformatics.hibernate.json;
+
+import java.util.HashSet;
+import java.util.Set;
+import com.marvinformatics.hibernate.json.model.Label;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.allOf;
+import static org.hamcrest.Matchers.containsInAnyOrder;
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.hasProperty;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.not;
+import static org.hamcrest.Matchers.sameInstance;
+
+public class JsonSetUserTypeTest {
+
+    private JsonSetUserType type = null;
+
+    @Before
+    public void createType() {
+        type = new JsonSetUserType() {
+            @Override
+            public Class<?> returnedClass() {
+                return Label.class;
+            }
+        };
+    }
+
+    @SuppressWarnings("unchecked")
+    @Test
+    public void testConvertJsonToObject() throws Exception {
+        String json = "[{\"value\": \"eclair\", \"lang\":\"fr\"}, {\"value\": \"saffron bun\", \"lang\":\"en\"}]";
+
+        Set<Label> labels = (Set<Label>) type.convertJsonToObject(json);
+
+        assertThat(labels, hasSize(2));
+        assertThat(labels, containsInAnyOrder(
+                allOf(hasProperty("value", is("eclair")), hasProperty("lang", is("fr"))),
+                allOf(hasProperty("value", is("saffron bun")), hasProperty("lang", is("en")))));
+    }
+
+    @Test
+    public void testConvertObjectToJson() throws Exception {
+        Set<Label> labels = new HashSet<>();
+        labels.add(new Label("eclair", "fr", 1));
+        labels.add(new Label("saffron bun", "en", 2));
+
+        String json = type.convertObjectToJson(labels);
+
+        assertThat(json, containsString("{\"value\":\"eclair\",\"lang\":\"fr\",\"order\":1}"));
+        assertThat(json, containsString("{\"value\":\"saffron bun\",\"lang\":\"en\",\"order\":2}"));
+    }
+
+    @SuppressWarnings("unchecked")
+    @Test
+    public void testDeepCopy() throws Exception {
+        Set<Label> labels = new HashSet<>();
+        labels.add(new Label("eclair", "fr", 3));
+        labels.add(new Label("saffron bun", "en", 4));
+
+        Set<Label> copy = (Set<Label>) type.deepCopy(labels);
+
+        assertThat(labels, hasSize(2));
+        assertThat(copy, equalTo(labels));
+        assertThat(copy, not(sameInstance(labels)));
+
+        assertThat(labels, containsInAnyOrder(
+                allOf(hasProperty("value", is("eclair")), hasProperty("lang", is("fr"))),
+                allOf(hasProperty("value", is("saffron bun")), hasProperty("lang", is("en")))));
+
+    }
+
+}