diff --git a/src/main/java/com/reandroid/arsc/array/StagedAliasEntryArray.java b/src/main/java/com/reandroid/arsc/array/StagedAliasEntryArray.java
index 8656f5f..9977738 100644
--- a/src/main/java/com/reandroid/arsc/array/StagedAliasEntryArray.java
+++ b/src/main/java/com/reandroid/arsc/array/StagedAliasEntryArray.java
@@ -34,6 +34,19 @@
          this.count=count;
          this.count.setBlockLoad(this);
      }
+     public boolean contains(StagedAliasEntry aliasEntry){
+         StagedAliasEntry[] childes=getChildes();
+         if(childes==null){
+             return false;
+         }
+         for(int i=0;i<childes.length;i++){
+             StagedAliasEntry entry=childes[i];
+             if(entry.isEqual(aliasEntry)){
+                 return true;
+             }
+         }
+         return false;
+     }
      public StagedAliasEntry searchByStagedResId(int stagedResId){
          StagedAliasEntry[] childes=getChildes();
          if(childes==null){
diff --git a/src/main/java/com/reandroid/arsc/chunk/Overlayable.java b/src/main/java/com/reandroid/arsc/chunk/Overlayable.java
index f21cec5..4e77c25 100644
--- a/src/main/java/com/reandroid/arsc/chunk/Overlayable.java
+++ b/src/main/java/com/reandroid/arsc/chunk/Overlayable.java
@@ -15,36 +15,53 @@
   */
  package com.reandroid.arsc.chunk;
 
- import com.reandroid.arsc.base.Block;
+ import com.reandroid.arsc.container.BlockList;
  import com.reandroid.arsc.header.HeaderBlock;
  import com.reandroid.arsc.header.OverlayableHeader;
- import com.reandroid.arsc.io.BlockLoad;
  import com.reandroid.arsc.io.BlockReader;
  import com.reandroid.arsc.item.ByteArray;
+ import com.reandroid.json.JSONArray;
+ import com.reandroid.json.JSONConvert;
+ import com.reandroid.json.JSONObject;
 
  import java.io.IOException;
+ import java.util.List;
 
  /**
   * Replica of struct "ResTable_overlayable_header" as on AOSP androidfw/ResourceTypes.h
   * We didn't test this class with resource table, if someone found a resource/apk please
   * create issue on https://github.com/REAndroid/ARSCLib
   * */
- public class Overlayable extends Chunk<OverlayableHeader> implements BlockLoad {
-     /**
-      * @link body
-      * As on AOSP there is only a description of header struct but no mention about
-      * chunk-content/body, thus we will use empty body byte array to avoid parse error
-      * */
-     private final ByteArray body;
+ public class Overlayable extends Chunk<OverlayableHeader> implements JSONConvert<JSONObject> {
+     private final BlockList<OverlayablePolicy> policyList;
+     private final ByteArray extraBytes;
+
      public Overlayable() {
-         super(new OverlayableHeader(), 1);
-         this.body = new ByteArray();
-         addChild(this.body);
-         getHeaderBlock().getActor().setBlockLoad(this);
+         super(new OverlayableHeader(), 2);
+         this.policyList = new BlockList<>();
+         this.extraBytes = new ByteArray();
+         addChild(this.policyList);
+         addChild(this.extraBytes);
      }
-     public ByteArray getBody() {
-         return body;
+
+     public OverlayablePolicy get(int flags){
+         for(OverlayablePolicy policy:listOverlayablePolicies()){
+             if(flags==policy.getFlags()){
+                 return policy;
+             }
+         }
+         return null;
      }
+     public void addOverlayablePolicy(OverlayablePolicy overlayablePolicy){
+         this.policyList.add(overlayablePolicy);
+     }
+     public List<OverlayablePolicy> listOverlayablePolicies() {
+         return policyList.getChildes();
+     }
+     public ByteArray getExtraBytes() {
+         return extraBytes;
+     }
+
      public String getName(){
          return getHeaderBlock().getName().get();
      }
@@ -57,22 +74,95 @@
      public void setActor(String str){
          getHeaderBlock().getActor().set(str);
      }
-     @Override
-     public void onBlockLoaded(BlockReader reader, Block sender) throws IOException {
-         if(sender==getHeaderBlock().getActor()){
-             HeaderBlock header = getHeaderBlock();
-             int bodySize=header.getChunkSize()-header.getHeaderSize();
-             this.body.setSize(bodySize);
-         }
-     }
+
      @Override
      protected void onChunkRefreshed() {
      }
+
+     @Override
+     public void onReadBytes(BlockReader reader) throws IOException {
+         HeaderBlock headerBlock = reader.readHeaderBlock();
+         checkInvalidChunk(headerBlock);
+
+         int size = headerBlock.getChunkSize();
+         BlockReader chunkReader = reader.create(size);
+         headerBlock = getHeaderBlock();
+         headerBlock.readBytes(chunkReader);
+
+         readOverlayablePlolicies(chunkReader);
+         readExtraBytes(chunkReader);
+
+         reader.offset(size);
+         chunkReader.close();
+         onChunkLoaded();
+     }
+     private void readOverlayablePlolicies(BlockReader reader) throws IOException {
+         HeaderBlock headerBlock = reader.readHeaderBlock();
+         BlockList<OverlayablePolicy> policyList = this.policyList;
+         while (headerBlock!=null && headerBlock.getChunkType()==ChunkType.OVERLAYABLE_POLICY){
+             OverlayablePolicy policy = new OverlayablePolicy();
+             policyList.add(policy);
+             policy.readBytes(reader);
+             headerBlock = reader.readHeaderBlock();
+         }
+     }
+     private void readExtraBytes(BlockReader reader) throws IOException {
+         int remaining = reader.available();
+         this.extraBytes.setSize(remaining);
+         this.extraBytes.readBytes(reader);
+     }
+
+     @Override
+     public JSONObject toJson() {
+         JSONObject jsonObject = new JSONObject();
+         jsonObject.put(NAME_name, getName());
+         jsonObject.put(NAME_actor, getActor());
+         JSONArray jsonArray = new JSONArray();
+         for(OverlayablePolicy policy:listOverlayablePolicies()){
+             jsonArray.put(policy);
+         }
+         return jsonObject;
+     }
+     @Override
+     public void fromJson(JSONObject json) {
+         setName(json.getString(NAME_name));
+         setActor(json.getString(NAME_actor));
+         JSONArray jsonArray = json.getJSONArray(NAME_policies);
+         int length = jsonArray.length();
+         BlockList<OverlayablePolicy> policyList = this.policyList;
+         for(int i=0;i<length;i++){
+             OverlayablePolicy policy = new OverlayablePolicy();
+             policyList.add(policy);
+             policy.fromJson(jsonArray.getJSONObject(i));
+         }
+     }
+     public void merge(Overlayable overlayable){
+         if(overlayable==null||overlayable==this){
+             return;
+         }
+         setName(overlayable.getName());
+         setActor(overlayable.getActor());
+         for(OverlayablePolicy policy:overlayable.listOverlayablePolicies()){
+             OverlayablePolicy exist = get(policy.getFlags());
+             if(exist==null){
+                 exist = new OverlayablePolicy();
+                 addOverlayablePolicy(exist);
+             }
+             exist.merge(policy);
+         }
+     }
+
      @Override
      public String toString(){
          return getClass().getSimpleName()+
-                 ": name='"+getName()
-                 +"', actor='"+getActor()
-                 +"', body-size="+getBody().size();
+                 ": name='" + getName()
+                 +"', actor='" + getActor()
+                 +"', policies=" + policyList.size()
+                 +"', extra=" + getExtraBytes().size();
      }
+
+     public static final String NAME_name = "name";
+     public static final String NAME_actor = "actor";
+     public static final String NAME_policies = "policies";
+
  }
diff --git a/src/main/java/com/reandroid/arsc/chunk/OverlayablePolicy.java b/src/main/java/com/reandroid/arsc/chunk/OverlayablePolicy.java
index 7f61583..328d811 100644
--- a/src/main/java/com/reandroid/arsc/chunk/OverlayablePolicy.java
+++ b/src/main/java/com/reandroid/arsc/chunk/OverlayablePolicy.java
@@ -21,6 +21,9 @@
  import com.reandroid.arsc.io.BlockReader;
  import com.reandroid.arsc.item.IntegerArray;
  import com.reandroid.arsc.item.IntegerItem;
+ import com.reandroid.json.JSONArray;
+ import com.reandroid.json.JSONConvert;
+ import com.reandroid.json.JSONObject;
 
  import java.io.IOException;
  import java.util.Collection;
@@ -30,7 +33,8 @@
   * We didn't test this class with resource table, if someone found a resource/apk please
   * create issue on https://github.com/REAndroid/ARSCLib
   * */
- public class OverlayablePolicy extends Chunk<OverlayablePolicyHeader> implements BlockLoad {
+ public class OverlayablePolicy extends Chunk<OverlayablePolicyHeader> implements BlockLoad,
+         JSONConvert<JSONObject> {
   private final IntegerArray tableRefArray;
   public OverlayablePolicy(){
    super(new OverlayablePolicyHeader(), 1);
@@ -81,6 +85,43 @@
     this.tableRefArray.setSize(entryCount.get());
    }
   }
+
+  @Override
+  public JSONObject toJson() {
+   JSONObject jsonObject = new JSONObject();
+   jsonObject.put(NAME_flags, getFlags());
+   JSONArray jsonArray = new JSONArray();
+   for(Integer reference:listTableReferences()){
+    jsonArray.put(reference);
+   }
+   jsonObject.put(NAME_references, jsonArray);
+   return jsonObject;
+  }
+  @Override
+  public void fromJson(JSONObject json) {
+   setFlags(json.getInt(NAME_flags));
+   JSONArray jsonArray = json.getJSONArray(NAME_references);
+   IntegerArray integerArray = getTableRefArray();
+   int length = jsonArray.length();
+   integerArray.setSize(length);
+   for(int i=0;i<length;i++){
+    integerArray.put(i, jsonArray.getInt(i));
+   }
+  }
+  public void merge(OverlayablePolicy policy){
+   if(policy==null||policy==this){
+    return;
+   }
+   setFlags(policy.getFlags());
+   IntegerArray exist = getTableRefArray();
+   IntegerArray coming = policy.getTableRefArray();
+   for(int reference: coming.toArray()){
+    if(!exist.contains(reference)){
+     exist.add(reference);
+    }
+   }
+  }
+
   @Override
   public String toString(){
    return getClass().getSimpleName()+
@@ -234,4 +275,7 @@
     return null;
    }
   }
+
+  public static final String NAME_flags = "flags";
+  public static final String NAME_references = "references";
  }
diff --git a/src/main/java/com/reandroid/arsc/chunk/PackageBlock.java b/src/main/java/com/reandroid/arsc/chunk/PackageBlock.java
index d871e6e..d10dbb4 100755
--- a/src/main/java/com/reandroid/arsc/chunk/PackageBlock.java
+++ b/src/main/java/com/reandroid/arsc/chunk/PackageBlock.java
@@ -25,6 +25,8 @@ package com.reandroid.arsc.chunk;
  import com.reandroid.arsc.group.EntryGroup;
  import com.reandroid.arsc.header.PackageHeader;
  import com.reandroid.arsc.item.ReferenceItem;
+ import com.reandroid.arsc.list.OverlayableList;
+ import com.reandroid.arsc.list.StagedAliasList;
  import com.reandroid.arsc.pool.SpecStringPool;
  import com.reandroid.arsc.pool.TableStringPool;
  import com.reandroid.arsc.pool.TypeStringPool;
@@ -32,6 +34,7 @@ package com.reandroid.arsc.chunk;
  import com.reandroid.arsc.value.LibraryInfo;
  import com.reandroid.arsc.value.ResConfig;
  import com.reandroid.arsc.value.StagedAliasEntry;
+ import com.reandroid.json.JSONArray;
  import com.reandroid.json.JSONConvert;
  import com.reandroid.json.JSONObject;
 
@@ -108,10 +111,10 @@ package com.reandroid.arsc.chunk;
     public List<StagedAlias> listStagedAlias(){
         return getStagedAliasList().getChildes();
     }
-    public BlockList<StagedAlias> getStagedAliasList(){
+    public StagedAliasList getStagedAliasList(){
         return mBody.getStagedAliasList();
     }
-    public BlockList<Overlayable> getOverlayableList(){
+    public OverlayableList getOverlayableList(){
         return mBody.getOverlayableList();
     }
     public BlockList<OverlayablePolicy> getOverlayablePolicyList(){
@@ -341,6 +344,10 @@ package com.reandroid.arsc.chunk;
             jsonObject.put(NAME_staged_aliases,
                     stagedAlias.getStagedAliasEntryArray().toJson());
         }
+        JSONArray jsonArray = getOverlayableList().toJson();
+        if(jsonArray!=null){
+            jsonObject.put(NAME_overlaybles, jsonArray);
+        }
         return jsonObject;
     }
     @Override
@@ -356,6 +363,9 @@ package com.reandroid.arsc.chunk;
                     .fromJson(json.getJSONArray(NAME_staged_aliases));
             getStagedAliasList().add(stagedAlias);
         }
+        if(json.has(NAME_overlaybles)){
+            getOverlayableList().fromJson(json.getJSONArray(NAME_overlaybles));
+        }
     }
     public void merge(PackageBlock packageBlock){
         if(packageBlock==null||packageBlock==this){
@@ -368,6 +378,8 @@ package com.reandroid.arsc.chunk;
         setName(packageBlock.getName());
         getLibraryBlock().merge(packageBlock.getLibraryBlock());
         getSpecTypePairArray().merge(packageBlock.getSpecTypePairArray());
+        getOverlayableList().merge(packageBlock.getOverlayableList());
+        getStagedAliasList().merge(packageBlock.getStagedAliasList());
     }
     /**
      * It is allowed to have duplicate type name therefore it is not recommend to use this.
@@ -400,7 +412,8 @@ package com.reandroid.arsc.chunk;
     public static final String NAME_package_id = "package_id";
     public static final String NAME_package_name = "package_name";
     public static final String JSON_FILE_NAME = "package.json";
-    private static final String NAME_specs="specs";
-    public static final String NAME_libraries="libraries";
-    public static final String NAME_staged_aliases="staged_aliases";
+    private static final String NAME_specs = "specs";
+    public static final String NAME_libraries = "libraries";
+    public static final String NAME_staged_aliases = "staged_aliases";
+    public static final String NAME_overlaybles = "overlaybles";
 }
diff --git a/src/main/java/com/reandroid/arsc/chunk/StagedAlias.java b/src/main/java/com/reandroid/arsc/chunk/StagedAlias.java
index d070ff9..ed1421f 100644
--- a/src/main/java/com/reandroid/arsc/chunk/StagedAlias.java
+++ b/src/main/java/com/reandroid/arsc/chunk/StagedAlias.java
@@ -34,8 +34,12 @@
          if(stagedAlias==null||stagedAlias==this){
              return;
          }
-         stagedAliasEntryArray.addAll(stagedAlias
-                 .getStagedAliasEntryArray().getChildes());
+         StagedAliasEntryArray exist = getStagedAliasEntryArray();
+         for(StagedAliasEntry entry:stagedAlias.listStagedAliasEntry()){
+             if(!exist.contains(entry)){
+                 exist.add(entry);
+             }
+         }
      }
      public StagedAliasEntryArray getStagedAliasEntryArray() {
          return stagedAliasEntryArray;
@@ -52,6 +56,7 @@
      }
      @Override
      protected void onChunkRefreshed() {
+         getHeaderBlock().getCount().set(getStagedAliasEntryCount());
      }
      @Override
      public String toString(){
diff --git a/src/main/java/com/reandroid/arsc/container/PackageBody.java b/src/main/java/com/reandroid/arsc/container/PackageBody.java
index 5236c04..c5e43b2 100755
--- a/src/main/java/com/reandroid/arsc/container/PackageBody.java
+++ b/src/main/java/com/reandroid/arsc/container/PackageBody.java
@@ -19,6 +19,8 @@ import com.reandroid.arsc.chunk.*;
 import com.reandroid.arsc.array.SpecTypePairArray;
 import com.reandroid.arsc.header.HeaderBlock;
 import com.reandroid.arsc.io.BlockReader;
+import com.reandroid.arsc.list.OverlayableList;
+import com.reandroid.arsc.list.StagedAliasList;
 
 import java.io.IOException;
 
@@ -26,16 +28,16 @@ public class PackageBody extends FixedBlockContainer {
 
     private final SpecTypePairArray mSpecTypePairArray;
     private final LibraryBlock mLibraryBlock;
-    private final BlockList<StagedAlias> mStagedAliasList;
-    private final BlockList<Overlayable> mOverlayableList;
+    private final StagedAliasList mStagedAliasList;
+    private final OverlayableList mOverlayableList;
     private final BlockList<OverlayablePolicy> mOverlayablePolicyList;
     private final BlockList<UnknownChunk> mUnknownChunkList;
     public PackageBody(){
         super(6);
         this.mSpecTypePairArray = new SpecTypePairArray();
         this.mLibraryBlock = new LibraryBlock();
-        this.mStagedAliasList = new BlockList<>();
-        this.mOverlayableList = new BlockList<>();
+        this.mStagedAliasList = new StagedAliasList();
+        this.mOverlayableList = new OverlayableList();
         this.mOverlayablePolicyList = new BlockList<>();
         this.mUnknownChunkList = new BlockList<>();
 
@@ -46,13 +48,13 @@ public class PackageBody extends FixedBlockContainer {
         addChild(4, mOverlayablePolicyList);
         addChild(5, mUnknownChunkList);
     }
-    public BlockList<Overlayable> getOverlayableList() {
+    public OverlayableList getOverlayableList() {
         return mOverlayableList;
     }
     public BlockList<OverlayablePolicy> getOverlayablePolicyList() {
         return mOverlayablePolicyList;
     }
-    public BlockList<StagedAlias> getStagedAliasList() {
+    public StagedAliasList getStagedAliasList() {
         return mStagedAliasList;
     }
     public LibraryBlock getLibraryBlock(){
diff --git a/src/main/java/com/reandroid/arsc/item/IntegerArray.java b/src/main/java/com/reandroid/arsc/item/IntegerArray.java
index 62c1b22..db3f926 100755
--- a/src/main/java/com/reandroid/arsc/item/IntegerArray.java
+++ b/src/main/java/com/reandroid/arsc/item/IntegerArray.java
@@ -23,9 +23,23 @@ public class IntegerArray extends BlockItem {
     public IntegerArray() {
         super(0);
     }
+    public final boolean contains(int value){
+        int s=size();
+        for(int i=0;i<s;i++){
+            if(value==get(i)){
+                return true;
+            }
+        }
+        return false;
+    }
     public final void clear(){
         setSize(0);
     }
+    public final void add(int value){
+        int old=size();
+        setSize(old+1);
+        put(old, value);
+    }
     public final void add(int[] values){
         if(values==null || values.length==0){
             return;
diff --git a/src/main/java/com/reandroid/arsc/list/OverlayableList.java b/src/main/java/com/reandroid/arsc/list/OverlayableList.java
new file mode 100644
index 0000000..800311d
--- /dev/null
+++ b/src/main/java/com/reandroid/arsc/list/OverlayableList.java
@@ -0,0 +1,73 @@
+ /*
+  *  Copyright (C) 2022 github.com/REAndroid
+  *
+  *  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.reandroid.arsc.list;
+
+import com.reandroid.arsc.chunk.Overlayable;
+import com.reandroid.arsc.container.BlockList;
+import com.reandroid.json.JSONArray;
+import com.reandroid.json.JSONConvert;
+import com.reandroid.json.JSONObject;
+
+public class OverlayableList extends BlockList<Overlayable> implements JSONConvert<JSONArray> {
+    public OverlayableList(){
+        super();
+    }
+    public Overlayable get(String name){
+        for(Overlayable overlayable:getChildes()){
+            if(name.equals(overlayable.getName())){
+                return overlayable;
+            }
+        }
+        return null;
+    }
+    @Override
+    public JSONArray toJson() {
+        if(size()==0){
+            return null;
+        }
+        JSONArray jsonArray = new JSONArray();
+        for(Overlayable overlayable:getChildes()){
+            JSONObject jsonOverlayble = overlayable.toJson();
+            jsonArray.put(jsonOverlayble);
+        }
+        return jsonArray;
+    }
+    @Override
+    public void fromJson(JSONArray json) {
+        if(json==null){
+            return;
+        }
+        int length = json.length();
+        for(int i=0;i<length;i++){
+            Overlayable overlayable = new Overlayable();
+            add(overlayable);
+            overlayable.fromJson(json.getJSONObject(i));
+        }
+    }
+    public void merge(OverlayableList overlayableList){
+        if(overlayableList==null || overlayableList==this){
+            return;
+        }
+        for(Overlayable overlayable: overlayableList.getChildes()){
+            Overlayable exist=get(overlayable.getName());
+            if(exist==null){
+                exist = new Overlayable();
+                add(exist);
+            }
+            exist.merge(overlayable);
+        }
+    }
+}
diff --git a/src/main/java/com/reandroid/arsc/list/StagedAliasList.java b/src/main/java/com/reandroid/arsc/list/StagedAliasList.java
new file mode 100644
index 0000000..581bd45
--- /dev/null
+++ b/src/main/java/com/reandroid/arsc/list/StagedAliasList.java
@@ -0,0 +1,46 @@
+ /*
+  *  Copyright (C) 2022 github.com/REAndroid
+  *
+  *  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.reandroid.arsc.list;
+
+import com.reandroid.arsc.chunk.StagedAlias;
+import com.reandroid.arsc.container.BlockList;
+
+public class StagedAliasList extends BlockList<StagedAlias> {
+    public StagedAliasList(){
+        super();
+    }
+    private StagedAlias pickOne(){
+        for(StagedAlias stagedAlias:getChildes()){
+            if(stagedAlias!=null){
+                return stagedAlias;
+            }
+        }
+        return null;
+    }
+    public void merge(StagedAliasList stagedAliasList){
+        if(stagedAliasList==null || stagedAliasList==this || stagedAliasList.size()==0){
+            return;
+        }
+        StagedAlias exist = pickOne();
+        if(exist==null){
+            exist=new StagedAlias();
+            add(exist);
+        }
+        for(StagedAlias stagedAlias:stagedAliasList.getChildes()){
+            exist.merge(stagedAlias);
+        }
+    }
+}
diff --git a/src/main/java/com/reandroid/arsc/value/StagedAliasEntry.java b/src/main/java/com/reandroid/arsc/value/StagedAliasEntry.java
index 55eeca5..72f5ee4 100644
--- a/src/main/java/com/reandroid/arsc/value/StagedAliasEntry.java
+++ b/src/main/java/com/reandroid/arsc/value/StagedAliasEntry.java
@@ -8,6 +8,16 @@ public class StagedAliasEntry extends ByteArray implements JSONConvert<JSONObjec
     public StagedAliasEntry(){
         super(8);
     }
+    public boolean isEqual(StagedAliasEntry other){
+        if(other==null){
+            return false;
+        }
+        if(other==this){
+            return true;
+        }
+        return getStagedResId()==other.getStagedResId()
+                && getFinalizedResId()==other.getFinalizedResId();
+    }
     public int getStagedResId(){
         return getInteger(0);
     }