hollow/src/main/java/com/netflix/hollow/core/read/engine/object/HollowObjectTypeReadState.java
public int bitsRequiredForField(String fieldName) {
        int maxBitsRequiredForField = shards[0].bitsRequiredForField(fieldName);
        
        for(int i=1;i<shards.length;i++) {
            int shardRequiredBits = shards[i].bitsRequiredForField(fieldName);
            if(shardRequiredBits > maxBitsRequiredForField)
                maxBitsRequiredForField = shardRequiredBits;
        }
        
        return maxBitsRequiredForField;
    }
public int bitsRequiredForField(String fieldName) {
        int maxBitsRequiredForField = shards[0].bitsRequiredForField(fieldName);
        
        for(int i=1;i<shards.length;i++) {
            int shardRequiredBits = shards[i].bitsRequiredForField(fieldName);
            if(shardRequiredBits > maxBitsRequiredForField)
                maxBitsRequiredForField = shardRequiredBits;
        }
        
        return maxBitsRequiredForField;
    }
Warning:  Not thread-safe.  Should only be called within the update thread.
@param fieldName the field name
@return the number of bits required for the field