Question

I am having an issue in getting the data in the below loop ,even though the size is not zero i am getting null in the sysout ‘data is’.What is wrong there ?

List<Long> dd = domainItemMapper.getIsSearchable(34372);
    System.out.println("the test is-" + dd.size());
    for (int i = 0; i < dd.size(); i++) {
        Long isSearch = dd.get(i);
        System.out.println("data is"+dd.get(i));
        if (isSearch.equals(0)) {
            isSearchValue = false;
        } else
            isSearchValue = true;
    }

The call to database is a mybatis call as below
interface

List<Long> getIsSearchable(@Param("parentFieldId") long parentFieldId);

impl

<mapper namespace="com.ge.dbt.common.persistence.IFormValidatorMapper">

        <select id="getIsSearchable" statementType="CALLABLE"
        resultType="Long">
        select is_searchable from t_field where parent_field_id=#{parentFieldId}
    </select>

</mapper>

Answer 1

I guess your whole code can be converted in to two lines.

if(dd!= null && !dd.isEmpty())
 return dd.contains(0);//Contains Guard you in such cases because equals check
                       //happen on passed element ie *0*

Default value of Long in java is null. So you will need additional check for null in your case.