Add support for transient fields

[cmelchior]

While looking into how to best support databinding, I ran across #4279 , which was easily fixable.
It doesn't make it possible to extend BaseObservable yet, but it is a step in the right direction.

[bmeike]

Looks good to me

[bmeike]

would this be clearer if it were an &&, as the previous test is an ||

[zaki50]

We should skip to transform the accesses to transient field.

Something like:

diff --git a/realm-transformer/src/main/groovy/io/realm/transformer/BytecodeModifier.groovy b/realm-transformer/src/main/groovy/io/realm/transformer/BytecodeModifier.groovy
index d64572ea3..e369ceddc 100644
--- a/realm-transformer/src/main/groovy/io/realm/transformer/BytecodeModifier.groovy
+++ b/realm-transformer/src/main/groovy/io/realm/transformer/BytecodeModifier.groovy
@@ -30,6 +30,10 @@ class BytecodeModifier {
 
     private static final Logger logger = LoggerFactory.getLogger('realm-logger')
 
+    static boolean isModelField(CtField field) {
+        !field.hasAnnotation(Ignore.class) && !Modifier.isTransient(field.getModifiers()) && !Modifier.isStatic(field.getModifiers())
+    }
+
     /**
      * Adds Realm specific accessors to a model class.
      * All the declared fields will be associated with a getter and a setter.
@@ -40,7 +44,7 @@ class BytecodeModifier {
         logger.debug "  Realm: Adding accessors to ${clazz.simpleName}"
         def methods = clazz.getDeclaredMethods()*.name
         clazz.declaredFields.each { CtField field ->
-            if (!Modifier.isStatic(field.getModifiers()) && !field.hasAnnotation(Ignore.class)) {
+            if (isModelField(field)) {
                 if (!methods.contains("realmGet\$${field.name}".toString())) {
                     clazz.addMethod(CtNewMethod.getter("realmGet\$${field.name}", field))
                 }
diff --git a/realm-transformer/src/main/groovy/io/realm/transformer/RealmTransformer.groovy b/realm-transformer/src/main/groovy/io/realm/transformer/RealmTransformer.groovy
index d7ca24a76..9a9ee08ac 100644
--- a/realm-transformer/src/main/groovy/io/realm/transformer/RealmTransformer.groovy
+++ b/realm-transformer/src/main/groovy/io/realm/transformer/RealmTransformer.groovy
@@ -22,7 +22,6 @@ import com.google.common.collect.ImmutableSet
 import com.google.common.collect.Sets
 import com.google.common.io.Files
 import groovy.io.FileType
-import io.realm.annotations.Ignore
 import io.realm.annotations.RealmClass
 import javassist.ClassPool
 import javassist.CtClass
@@ -30,7 +29,6 @@ import org.gradle.api.Project
 import org.slf4j.Logger
 import org.slf4j.LoggerFactory
 
-import java.lang.reflect.Modifier
 import java.util.jar.JarFile
 import java.util.regex.Pattern
 
@@ -121,7 +119,7 @@ class RealmTransformer extends Transform {
         def allManagedFields = []
         allModelClasses.each {
             allManagedFields.addAll(it.declaredFields.findAll {
-                !it.hasAnnotation(Ignore.class) && !Modifier.isStatic(it.getModifiers())
+                BytecodeModifier.isModelField(it)
             })
         }
         logger.debug "Managed Fields: ${allManagedFields*.name}"

[cmelchior]

Good catch @zaki50. I'll adjust that.

[cmelchior]

Updated @zaki50

[zaki50]

👍
But still needs another 👍 since this PR contains my code 😃

[beeender]

RealmObject.java javadoc needs to be fixed:

The only restriction a RealmObject has is that fields are not allowed to be final, transient' or volatile.

Other than this, 👍

[beeender]

👍