OJRestApplications now provide a JSON serialization mechanism for OJB…

…eans

ojcms-sqldatasource/src/main/java/de/adito/ojcms/sql/datasource/util/BeanSerializationException.java → ojcms-beans/src/main/java/de/adito/ojcms/beans/exceptions/bean/BeanSerializationException.java

@@ -1,4 +1,4 @@
-package de.adito.ojcms.sql.datasource.util;
+package de.adito.ojcms.beans.exceptions.bean;
 
 /**
  * Exception for bean serialization problems.
@@ -20,10 +20,11 @@ public BeanSerializationException(String pMessage)
   /**
    * Creates a new serialization exception.
    *
-   * @param pThrowable the cause for the exception
+   * @param pMessage   a detailed error message
+   * @param pThrowable the cause of the exception
    */
-  public BeanSerializationException(Throwable pThrowable)
+  public BeanSerializationException(String pMessage, Throwable pThrowable)
   {
-    super(pThrowable);
+    super(pMessage, pThrowable);
   }
 }

ojcms-rest/ojcms-rest-server/src/main/java/de/adito/ojcms/rest/application/OJRestApplication.java

@@ -1,6 +1,6 @@
 package de.adito.ojcms.rest.application;
 
-import de.adito.ojcms.rest.serialization.GSONSerializationProvider;
+import de.adito.ojcms.rest.serialization.*;
 
 import javax.ws.rs.*;
 import javax.ws.rs.core.Application;
@@ -36,6 +36,7 @@ protected OJRestApplication(Class<?>... pRestResources)
     }
 
     providerAndResourceTypes.add(GSONSerializationProvider.class);
+    providerAndResourceTypes.add(BeanSerializationProvider.class);
   }
 
   @Override

ojcms-rest/ojcms-rest-server/src/main/java/de/adito/ojcms/rest/serialization/BeanSerializationProvider.java

@@ -0,0 +1,102 @@
+package de.adito.ojcms.rest.serialization;
+
+import de.adito.ojcms.beans.IBean;
+import de.adito.ojcms.beans.exceptions.bean.BeanSerializationException;
+import de.adito.ojcms.beans.literals.fields.serialization.ISerializableField;
+import sun.reflect.generics.reflectiveObjects.ParameterizedTypeImpl;
+
+import javax.ws.rs.*;
+import javax.ws.rs.core.*;
+import javax.ws.rs.ext.*;
+import java.io.*;
+import java.lang.annotation.Annotation;
+import java.lang.reflect.*;
+import java.util.Map;
+
+import static de.adito.ojcms.rest.auth.util.GSONFactory.GSON;
+import static java.util.stream.Collectors.toMap;
+
+/**
+ * JSON serialization provider for {@link IBean} instances. Only possible for beans that contain {@link ISerializableField} only.
+ *
+ * @author Simon Danner, 21.04.2020
+ */
+@Provider
+@Consumes(MediaType.APPLICATION_JSON)
+@Produces(MediaType.APPLICATION_JSON)
+public class BeanSerializationProvider implements MessageBodyReader<IBean>, MessageBodyWriter<IBean>
+{
+  @Override
+  public boolean isReadable(Class<?> pType, Type pGenericType, Annotation[] pAnnotations, MediaType pMediaType)
+  {
+    return true;
+  }
+
+  @Override
+  public IBean readFrom(Class<IBean> pType, Type pGenericType, Annotation[] pAnnotations, MediaType pMediaType,
+      MultivaluedMap<String, String> pHttpHeaders, InputStream pEntityStream) throws IOException, WebApplicationException
+  {
+    try (InputStreamReader reader = new InputStreamReader(pEntityStream))
+    {
+      final ParameterizedType mapType = ParameterizedTypeImpl.make(Map.class, new Type[]{String.class, Serializable.class}, IBean.class);
+      final Map<String, Serializable> serialBeanValues = GSON.fromJson(reader, mapType);
+
+      try
+      {
+        final IBean bean = createEmptyBeanInstance(pType);
+        for (Map.Entry<String, Serializable> entry : serialBeanValues.entrySet())
+        {
+          final ISerializableField field = (ISerializableField) bean.getFieldByName(entry.getKey());
+          //noinspection unchecked
+          bean.setValue(field, field.fromPersistent(entry.getValue()));
+        }
+
+        return bean;
+      }
+      catch (IllegalAccessException | InvocationTargetException | InstantiationException | NoSuchMethodException pE)
+      {
+        throw new BeanSerializationException("Provide a default constructor for " + pType.getName() + "! May be private!", pE);
+      }
+    }
+  }
+
+  @Override
+  public boolean isWriteable(Class<?> pType, Type pGenericType, Annotation[] pAnnotations, MediaType pMediaType)
+  {
+    return true;
+  }
+
+  @Override
+  public void writeTo(IBean pBean, Class<?> pType, Type pGenericType, Annotation[] pAnnotations, MediaType pMediaType,
+      MultivaluedMap<String, Object> pHttpHeaders, OutputStream pEntityStream) throws IOException, WebApplicationException
+  {
+    if (pBean.streamFields().allMatch(pField -> pField instanceof ISerializableField))
+      throw new BeanSerializationException("Bean of type " + pType.getName() + " has non serializable fields!");
+
+    //noinspection unchecked
+    final Map<String, Serializable> serialBeanValues = pBean.stream() //
+        .collect(toMap(pTuple -> pTuple.getField().getName(),
+            pTuple -> ((ISerializableField) pTuple.getField()).toPersistent(pTuple.getValue())));
+
+    try (PrintWriter writer = new PrintWriter(pEntityStream))
+    {
+      writer.write(GSON.toJson(serialBeanValues));
+    }
+  }
+
+  /**
+   * Creates an empty bean instance by calling its default constructor.
+   *
+   * @param pBeanType the bean type to instantiate
+   * @return the create bean instance
+   */
+  private static IBean createEmptyBeanInstance(Class<IBean> pBeanType)
+      throws IllegalAccessException, InvocationTargetException, InstantiationException, NoSuchMethodException
+  {
+    final Constructor<IBean> defaultConstructor = pBeanType.getDeclaredConstructor();
+    if (!defaultConstructor.isAccessible())
+      defaultConstructor.setAccessible(true);
+
+    return defaultConstructor.newInstance();
+  }
+}

ojcms-rest/ojcms-rest-server/src/main/java/de/adito/ojcms/rest/serialization/GSONSerializationProvider.java

@@ -24,32 +24,32 @@
 public class GSONSerializationProvider implements MessageBodyReader<Object>, MessageBodyWriter<Object>
 {
   @Override
-  public boolean isReadable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType)
+  public boolean isReadable(Class<?> pType, Type pGenericType, Annotation[] pAnnotations, MediaType pMediaType)
   {
     return true;
   }
 
   @Override
-  public Object readFrom(Class<Object> type, Type genericType, Annotation[] annotations, MediaType mediaType,
-      MultivaluedMap<String, String> httpHeaders, InputStream entityStream) throws IOException, WebApplicationException
+  public Object readFrom(Class<Object> pType, Type pGenericType, Annotation[] pAnnotations, MediaType pMediaType,
+      MultivaluedMap<String, String> pHttpHeaders, InputStream pEntityStream) throws IOException, WebApplicationException
   {
-    try (InputStreamReader reader = new InputStreamReader(entityStream))
+    try (InputStreamReader reader = new InputStreamReader(pEntityStream))
     {
-      return GSON.fromJson(reader, type);
+      return GSON.fromJson(reader, pType);
     }
   }
 
   @Override
-  public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType)
+  public boolean isWriteable(Class<?> pType, Type pGenericType, Annotation[] pAnnotations, MediaType pMediaType)
   {
     return true;
   }
 
   @Override
-  public void writeTo(Object pObject, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType,
-      MultivaluedMap<String, Object> httpHeaders, OutputStream entityStream) throws WebApplicationException
+  public void writeTo(Object pObject, Class<?> pType, Type pGenericType, Annotation[] pAnnotations, MediaType pMediaType,
+      MultivaluedMap<String, Object> pHttpHeaders, OutputStream pEntityStream) throws WebApplicationException
   {
-    try (PrintWriter writer = new PrintWriter(entityStream))
+    try (PrintWriter writer = new PrintWriter(pEntityStream))
     {
       writer.write(GSON.toJson(pObject));
     }

ojcms-sqldatasource/src/main/java/de/adito/ojcms/sql/datasource/util/BeanSQLSerializer.java

@@ -1,5 +1,6 @@
 package de.adito.ojcms.sql.datasource.util;
 
+import de.adito.ojcms.beans.exceptions.bean.BeanSerializationException;
 import de.adito.ojcms.beans.literals.fields.IField;
 import de.adito.ojcms.beans.literals.fields.serialization.ISerializableField;
 import de.adito.ojcms.beans.literals.fields.util.*;