Added @FieldOrder for bean fields to define their declaration order m…

…anually (since some JVM implementations do not provide them in the right order naturally)

ojcms-beans/src/main/java/de/adito/ojcms/beans/annotations/FieldOrder.java

@@ -0,0 +1,25 @@
+package de.adito.ojcms.beans.annotations;
+
+import java.lang.annotation.*;
+
+/**
+ * Use this annotation for bean fields to define their declaration order. This is necessary if you are using a JVM implementation that
+ * does not provide fields in their declaration order naturally (via {@link Class#getDeclaredFields()}.
+ * <p>
+ * If this annotation is used at least for one bean field, all other fields must be annotated as well. Otherwise a runtime exception will
+ * be thrown. The order numbers for a bean class must not contain duplicates, but may have gaps (like 100, 200, 300, ...).
+ * <p>
+ * Lower numbers are declared before higher numbers.
+ *
+ * @author Simon Danner, 11.06.2020
+ */
+@Documented
+@Target(ElementType.FIELD)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface FieldOrder
+{
+  /**
+   * A number indicating the declaration position of the annotated bean field (lower number = lower position)
+   */
+  int value();
+}

ojcms-beans/src/main/java/de/adito/ojcms/beans/exceptions/field/BeanFieldDuplicateException.java

@@ -22,7 +22,7 @@ public BeanFieldDuplicateException(List<IField<?>> pDuplicateFields)
   {
     super("A bean cannot define a field twice! duplicates: " + pDuplicateFields.stream() //
         .map(IField::getName) //
-        .collect(Collectors.joining(", ")));
+        .collect(Collectors.joining(", ")) + "\n Take a look at @FieldOrder as well!");
   }
 
   /**

ojcms-beans/src/main/java/de/adito/ojcms/beans/util/BeanReflector.java

@@ -1,8 +1,10 @@
 package de.adito.ojcms.beans.util;
 
 import de.adito.ojcms.beans.*;
+import de.adito.ojcms.beans.annotations.FieldOrder;
 import de.adito.ojcms.beans.exceptions.OJInternalException;
 import de.adito.ojcms.beans.exceptions.bean.NoDeclaredBeanTypeException;
+import de.adito.ojcms.beans.exceptions.field.BeanFieldCreationException;
 import de.adito.ojcms.beans.literals.fields.IField;
 
 import java.lang.annotation.Annotation;
@@ -87,7 +89,7 @@ public static Class<? extends IBean> requiresDeclaredBeanType(Class<? extends IB
    * @param <ANNOTATION>    the generic type of the annotation
    */
   public static <ANNOTATION extends Annotation> void doIfAnnotationPresent(Class<?> pType, Class<ANNOTATION> pAnnotationType,
-                                                                           Consumer<ANNOTATION> pAction)
+      Consumer<ANNOTATION> pAction)
   {
     if (pType.isAnnotationPresent(pAnnotationType))
       pAction.accept(pType.getAnnotation(pAnnotationType));
@@ -117,16 +119,47 @@ private static List<IField<?>> _createBeanMetadata(Class<? extends IBean> pBeanT
   }
 
   /**
-   * Returns all public and static bean fields from a bean class type.
+   * Returns all public, static and final bean fields from a bean class type. This method must return the fields in their textual
+   * declaration order. If the JVM implementation won't do that naturally, use {@link FieldOrder}.
    *
    * @param pBeanType the type of the bean, which must be a sub class of {@link OJBean} to own specific fields
    * @return a list of declared fields of the bean type
    */
   private static List<Field> _getDeclaredBeanFields(Class<? extends IBean> pBeanType)
   {
-    return _getDeclaredFields(pBeanType,  //
+    final List<Field> unsortedDeclaredFields = _getDeclaredFields(pBeanType,  //
         pField -> Modifier.isStatic(pField.getModifiers()), //
         pField -> IField.class.isAssignableFrom(pField.getType()));
+
+    final Map<Field, Integer> fieldOrderByField = new HashMap<>();
+
+    for (Field field : unsortedDeclaredFields)
+    {
+      if (!Modifier.isFinal(field.getModifiers()))
+        throw new BeanFieldCreationException(
+            "Bean field is not declared as final! bean-type: " + pBeanType.getName() + " field name: " + field.getName());
+
+      if (field.isAnnotationPresent(FieldOrder.class))
+        fieldOrderByField.put(field, field.getAnnotation(FieldOrder.class).value());
+    }
+
+    if (fieldOrderByField.isEmpty())
+      return unsortedDeclaredFields; //They should be sorted naturally by JVM implementation
+
+    //Does every field have a field order annotation?
+    if (fieldOrderByField.size() != unsortedDeclaredFields.size())
+      throw new BeanFieldCreationException(
+          "If @FieldOrder is used, every field of the bean type must be annotated! bean-type: " + pBeanType.getName());
+
+    //Check for duplicates in order numbers
+    final Set<Integer> uniqueOrderNumbers = new HashSet<>(fieldOrderByField.values());
+    if (uniqueOrderNumbers.size() != fieldOrderByField.size())
+      throw new BeanFieldCreationException("All order numbers of @FieldOrders must be unique!");
+
+    return fieldOrderByField.entrySet().stream() //
+        .sorted(Map.Entry.comparingByValue()) //
+        .map(Map.Entry::getKey) //
+        .collect(Collectors.toList());
   }
 
   /**

ojcms-beans/src/test/java/de/adito/ojcms/beans/BeanTest.java

@@ -4,7 +4,7 @@
 import de.adito.ojcms.beans.base.IEqualsHashCodeChecker;
 import de.adito.ojcms.beans.datasource.IBeanDataSource;
 import de.adito.ojcms.beans.exceptions.bean.*;
-import de.adito.ojcms.beans.exceptions.field.BeanFieldDoesNotExistException;
+import de.adito.ojcms.beans.exceptions.field.*;
 import de.adito.ojcms.beans.literals.fields.IField;
 import de.adito.ojcms.beans.literals.fields.types.*;
 import de.adito.ojcms.beans.literals.fields.util.FieldValueTuple;
@@ -210,6 +210,30 @@ public void testBeanInheritance()
     assertEquals(42, bean.getValue(ConcreteBeanType.SOME_SPECIAL_FIELD));
   }
 
+  @Test
+  public void testBeanFieldOrderDeclaration()
+  {
+    new FieldOrderedBean();
+  }
+
+  @Test
+  public void testBeanFieldOrderDeclaration_Illegal()
+  {
+    assertThrows(BeanFieldDuplicateException.class, IllegalOrderedBean::new);
+  }
+
+  @Test
+  public void testBeanFieldOrderDeclaration_MissingAnnotation()
+  {
+    assertThrows(ExceptionInInitializerError.class, MissingOrderAnnotationBean::new);
+  }
+
+  @Test
+  public void testBeanFieldOrderDeclaration_Duplicate()
+  {
+    assertThrows(ExceptionInInitializerError.class, DuplicateOrderAnnotationBean::new);
+  }
+
   /**
    * Creates a new bean text field.
    *
@@ -340,6 +364,51 @@ public static class ConcreteBeanType extends AbstractBaseBeanType
     public static final IntegerField SOME_SPECIAL_FIELD = OJFields.create(ConcreteBeanType.class);
   }
 
+  /**
+   * A bean defining its fields' declaration order.
+   */
+  public static class FieldOrderedBean extends OJBean
+  {
+    @FieldOrder(0)
+    public static final IntegerField FIRST_FIELD = OJFields.create(FieldOrderedBean.class);
+    @FieldOrder(1)
+    public static final IntegerField SECOND_FIELD = OJFields.create(FieldOrderedBean.class);
+    @FieldOrder(4) //Gaps should be allowed
+    public static final IntegerField THIRD_FIELD = OJFields.create(FieldOrderedBean.class);
+  }
+
+  /**
+   * A bean defining a wrong/illegal declaration order.
+   */
+  public static class IllegalOrderedBean extends OJBean
+  {
+    @FieldOrder(1)
+    public static final IntegerField FIRST_FIELD = OJFields.create(IllegalOrderedBean.class);
+    @FieldOrder(0)
+    public static final IntegerField SECOND_FIELD = OJFields.create(IllegalOrderedBean.class);
+  }
+
+  /**
+   * A bean missing a field order annotation.
+   */
+  public static class MissingOrderAnnotationBean extends OJBean
+  {
+    @FieldOrder(0)
+    public static final IntegerField FIRST_FIELD = OJFields.create(MissingOrderAnnotationBean.class);
+    public static final IntegerField SECOND_FIELD = OJFields.create(MissingOrderAnnotationBean.class);
+  }
+
+  /**
+   * A bean defining a duplicate field order annotation.
+   */
+  public static class DuplicateOrderAnnotationBean extends OJBean
+  {
+    @FieldOrder(0)
+    public static final IntegerField FIRST_FIELD = OJFields.create(DuplicateOrderAnnotationBean.class);
+    @FieldOrder(0)
+    public static final IntegerField SECOND_FIELD = OJFields.create(DuplicateOrderAnnotationBean.class);
+  }
+
   /**
    * A bean data source that always returns null values to test {@link NeverNull} fields.
    */

ojcms-persistence/src/test/java/de/adito/ojcms/persistence/PersistentBaseContainerTest.java

@@ -66,10 +66,10 @@ public void testBaseContainerWithPresetContent()
   public static abstract class SomeBaseBean extends OJBean
   {
     @Identifier
-    public static IntegerField FIELD1 = OJFields.create(SomeBaseBean.class);
+    public static final IntegerField FIELD1 = OJFields.create(SomeBaseBean.class);
     @Identifier
-    public static LongField FIELD2 = OJFields.create(SomeBaseBean.class);
-    public static BooleanField FIELD3 = OJFields.create(SomeBaseBean.class);
+    public static final LongField FIELD2 = OJFields.create(SomeBaseBean.class);
+    public static final BooleanField FIELD3 = OJFields.create(SomeBaseBean.class);
 
     SomeBaseBean(int pValue1, long pValue2, boolean pValue3)
     {
@@ -85,7 +85,7 @@ private SomeBaseBean()
 
   public static class SomeConcreteBean extends SomeBaseBean
   {
-    public static TextField FIELD4 = OJFields.create(SomeConcreteBean.class);
+    public static final TextField FIELD4 = OJFields.create(SomeConcreteBean.class);
 
     SomeConcreteBean(int pValue1, long pValue2, boolean pValue3, String pValue4)
     {
@@ -101,8 +101,8 @@ private SomeConcreteBean()
 
   public static class SomeOtherConcreteBean extends SomeBaseBean
   {
-    public static TextField FIELD5 = OJFields.create(SomeOtherConcreteBean.class);
-    public static TimestampField FIELD6 = OJFields.create(SomeOtherConcreteBean.class);
+    public static final TextField FIELD5 = OJFields.create(SomeOtherConcreteBean.class);
+    public static final TimestampField FIELD6 = OJFields.create(SomeOtherConcreteBean.class);
 
     SomeOtherConcreteBean(int pValue1, long pValue2, boolean pValue3, String pValue5)
     {

ojcms-rest/ojcms-auth-api/src/main/java/de/adito/ojcms/rest/auth/api/AuthenticationRequest.java

@@ -1,7 +1,7 @@
 package de.adito.ojcms.rest.auth.api;
 
 import de.adito.ojcms.beans.*;
-import de.adito.ojcms.beans.annotations.FinalNeverNull;
+import de.adito.ojcms.beans.annotations.*;
 import de.adito.ojcms.beans.literals.fields.types.TextField;
 
 /**
@@ -12,8 +12,11 @@
 public class AuthenticationRequest extends OJBean
 {
   @FinalNeverNull
+  @FieldOrder(0)
   public static final TextField USER_MAIL = OJFields.create(AuthenticationRequest.class);
+
   @FinalNeverNull
+  @FieldOrder(1)
   public static final TextField PASSWORD = OJFields.create(AuthenticationRequest.class);
 
   public AuthenticationRequest(String pUserMail, String pPassword)

ojcms-rest/ojcms-auth-api/src/main/java/de/adito/ojcms/rest/auth/api/AuthenticationResponse.java

@@ -1,7 +1,7 @@
 package de.adito.ojcms.rest.auth.api;
 
 import de.adito.ojcms.beans.*;
-import de.adito.ojcms.beans.annotations.FinalNeverNull;
+import de.adito.ojcms.beans.annotations.*;
 import de.adito.ojcms.beans.literals.fields.types.TextField;
 
 /**
@@ -14,9 +14,12 @@
 public class AuthenticationResponse extends OJBean
 {
   @FinalNeverNull
-  public static TextField TOKEN = OJFields.create(AuthenticationResponse.class);
+  @FieldOrder(0)
+  public static final TextField TOKEN = OJFields.create(AuthenticationResponse.class);
+
   @FinalNeverNull
-  public static TextField NEXT_PASSWORD = OJFields.create(AuthenticationResponse.class);
+  @FieldOrder(1)
+  public static final TextField NEXT_PASSWORD = OJFields.create(AuthenticationResponse.class);
 
   public AuthenticationResponse(String pToken, String pNextPassword)
   {

ojcms-rest/ojcms-auth-api/src/main/java/de/adito/ojcms/rest/auth/api/RegistrationRequest.java

@@ -1,7 +1,7 @@
 package de.adito.ojcms.rest.auth.api;
 
 import de.adito.ojcms.beans.*;
-import de.adito.ojcms.beans.annotations.FinalNeverNull;
+import de.adito.ojcms.beans.annotations.*;
 import de.adito.ojcms.beans.literals.fields.types.TextField;
 
 /**
@@ -12,9 +12,12 @@
 public class RegistrationRequest extends OJBean
 {
   @FinalNeverNull
-  public static TextField USER_MAIL = OJFields.create(RegistrationRequest.class);
+  @FieldOrder(0)
+  public static final TextField USER_MAIL = OJFields.create(RegistrationRequest.class);
+
   @FinalNeverNull
-  public static TextField DISPLAY_NAME = OJFields.create(RegistrationRequest.class);
+  @FieldOrder(1)
+  public static final TextField DISPLAY_NAME = OJFields.create(RegistrationRequest.class);
 
   public RegistrationRequest(String pUserMail, String pDisplayName)
   {

ojcms-rest/ojcms-auth-api/src/main/java/de/adito/ojcms/rest/auth/api/RestoreAuthenticationRequest.java

@@ -1,7 +1,7 @@
 package de.adito.ojcms.rest.auth.api;
 
 import de.adito.ojcms.beans.*;
-import de.adito.ojcms.beans.annotations.FinalNeverNull;
+import de.adito.ojcms.beans.annotations.*;
 import de.adito.ojcms.beans.literals.fields.types.TextField;
 
 /**
@@ -12,9 +12,12 @@
 public final class RestoreAuthenticationRequest extends OJBean
 {
   @FinalNeverNull
-  public static TextField USER_MAIL = OJFields.create(RestoreAuthenticationRequest.class);
+  @FieldOrder(0)
+  public static final TextField USER_MAIL = OJFields.create(RestoreAuthenticationRequest.class);
+
   @FinalNeverNull
-  public static TextField RESTORE_CODE = OJFields.create(RestoreAuthenticationRequest.class);
+  @FieldOrder(1)
+  public static final TextField RESTORE_CODE = OJFields.create(RestoreAuthenticationRequest.class);
 
   /**
    * Creates a new restore request.

ojcms-rest/ojcms-rest-server/src/test/java/de/adito/ojcms/rest/testapplication/RegistrationRequestForTest.java

@@ -1,7 +1,7 @@
 package de.adito.ojcms.rest.testapplication;
 
 import de.adito.ojcms.beans.OJFields;
-import de.adito.ojcms.beans.annotations.FinalNeverNull;
+import de.adito.ojcms.beans.annotations.*;
 import de.adito.ojcms.beans.literals.fields.types.EnumField;
 import de.adito.ojcms.rest.auth.api.RegistrationRequest;
 
@@ -13,6 +13,7 @@
 public class RegistrationRequestForTest extends RegistrationRequest
 {
   @FinalNeverNull
+  @FieldOrder(2)
   public static final EnumField<EUserRoleForTest> USER_ROLE = OJFields.create(RegistrationRequestForTest.class);
 
   public RegistrationRequestForTest(String pUserMail, String pDisplayName, EUserRoleForTest pUserRole)