adding support for @JsonBackreference (#24)

monitorjbl · Jun 7, 2016 · a1d3ae9 · a1d3ae9
1 parent 0a13818
commit a1d3ae9
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Showing 3 changed files with 90 additions and 2 deletions.
diff --git a/json-view/src/main/java/com/monitorjbl/json/JsonViewSerializer.java b/json-view/src/main/java/com/monitorjbl/json/JsonViewSerializer.java
@@ -1,8 +1,10 @@
 package com.monitorjbl.json;
 
+import com.fasterxml.jackson.annotation.JsonBackReference;
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import com.fasterxml.jackson.annotation.JsonInclude.Include;
+import com.fasterxml.jackson.annotation.JsonManagedReference;
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.databind.JsonSerializer;
 import com.fasterxml.jackson.databind.SerializerProvider;
@@ -244,7 +246,8 @@ boolean valueAllowed(Object value, Class cls) {
           || (serializerProvider.getConfig() != null
           && serializerProvider.getConfig().getSerializationInclusion() == Include.ALWAYS
           && cls.getAnnotation(JsonSerialize.class) == null)
-          || (cls.getAnnotation(JsonSerialize.class) != null && readClassAnnotation(cls, JsonSerialize.class, "include") == Inclusion.ALWAYS);
+          || (cls.getAnnotation(JsonSerialize.class) != null
+          && readClassAnnotation(cls, JsonSerialize.class, "include") == Inclusion.ALWAYS);
     }
 
     @SuppressWarnings("unchecked")
@@ -362,13 +365,28 @@ boolean annotatedWithIgnore(Field f) {
       JsonIgnore jsonIgnore = f.getAnnotation(JsonIgnore.class);
       JsonIgnoreProperties classIgnoreProperties = f.getDeclaringClass().getAnnotation(JsonIgnoreProperties.class);
       JsonIgnoreProperties fieldIgnoreProperties = null;
+      boolean backReferenced = false;
+
+      //make sure the referring field didn't specify properties to ignore
       if(referringField != null) {
         fieldIgnoreProperties = referringField.getAnnotation(JsonIgnoreProperties.class);
       }
 
+      //make sure the referring field didn't specify a backreference annotation
+      if(f.getAnnotation(JsonBackReference.class) != null && referringField != null) {
+        for(Field lastField : referringField.getDeclaringClass().getDeclaredFields()) {
+          JsonManagedReference fieldManagedReference = lastField.getAnnotation(JsonManagedReference.class);
+          if(fieldManagedReference != null && lastField.getType().equals(f.getDeclaringClass())) {
+            backReferenced = true;
+            break;
+          }
+        }
+      }
+
       return (jsonIgnore != null && jsonIgnore.value()) ||
           (classIgnoreProperties != null && Arrays.asList(classIgnoreProperties.value()).contains(f.getName())) ||
-          (fieldIgnoreProperties != null && Arrays.asList(fieldIgnoreProperties.value()).contains(f.getName()));
+          (fieldIgnoreProperties != null && Arrays.asList(fieldIgnoreProperties.value()).contains(f.getName())) ||
+          backReferenced;
     }
 
     @SuppressWarnings("unchecked")

diff --git a/json-view/src/test/java/com/monitorjbl/json/JsonViewSerializerTest.java b/json-view/src/test/java/com/monitorjbl/json/JsonViewSerializerTest.java
@@ -7,6 +7,8 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.common.io.BaseEncoding;
 import com.google.common.primitives.Ints;
+import com.monitorjbl.json.model.TestBackreferenceObject;
+import com.monitorjbl.json.model.TestBackreferenceObject.TestForwardReferenceObject;
 import com.monitorjbl.json.model.TestChildObject;
 import com.monitorjbl.json.model.TestNonNulls;
 import com.monitorjbl.json.model.TestNulls;
@@ -670,4 +672,20 @@ public void testIgnorePropertiesOnField() throws Exception {
     assertNotNull(obj.get("subWithIgnores").get("otherVal"));
     assertNull(obj.get("subWithIgnores").get("val"));
   }
+
+  @Test
+  public void testBackReferenceSupport() throws Exception {
+    TestForwardReferenceObject forward = new TestForwardReferenceObject();
+    TestBackreferenceObject back = new TestBackreferenceObject();
+
+    forward.setId("forward");
+    forward.setParent(back);
+    back.setId("back");
+    back.setChildren(asList(forward));
+
+    String serialized = sut.writeValueAsString(JsonView.with(forward));
+    Map<String, Map<String, Object>> obj = sut.readValue(serialized, HashMap.class);
+
+    System.out.println(obj);
+  }
 }
diff --git a/json-view/src/test/java/com/monitorjbl/json/model/TestBackreferenceObject.java b/json-view/src/test/java/com/monitorjbl/json/model/TestBackreferenceObject.java
@@ -0,0 +1,52 @@
+package com.monitorjbl.json.model;
+
+import com.fasterxml.jackson.annotation.JsonBackReference;
+import com.fasterxml.jackson.annotation.JsonManagedReference;
+
+import java.util.List;
+
+public class TestBackreferenceObject {
+
+  private String id;
+  @JsonBackReference
+  private List<TestForwardReferenceObject> children;
+
+
+  public String getId() {
+    return id;
+  }
+
+  public void setId(String id) {
+    this.id = id;
+  }
+
+  public List<TestForwardReferenceObject> getChildren() {
+    return children;
+  }
+
+  public void setChildren(List<TestForwardReferenceObject> children) {
+    this.children = children;
+  }
+
+  public static class TestForwardReferenceObject{
+    private String id;
+    @JsonManagedReference
+    private TestBackreferenceObject parent;
+
+    public String getId() {
+      return id;
+    }
+
+    public void setId(String id) {
+      this.id = id;
+    }
+
+    public TestBackreferenceObject getParent() {
+      return parent;
+    }
+
+    public void setParent(TestBackreferenceObject parent) {
+      this.parent = parent;
+    }
+  }
+}