Do you know - Series 1: Null Check: Java

The idea of this post is to just highlight some of the features in Java which we may need in our day to day development work.

• The different ways to check null value of an Object

• null != obj

• Objects.nonNull(obj) - from java.util

• filter(Objects::nonNull) - when used with Lambda

• Optional.ofNullable(obj).ifPresent(o —> o.getValue());

• StringUtils.isNotEmpty(obj) - from org.apache.commons.lang3
• this takes care of both empty and null checks

• filter(StringUtils::isNotEmpty) - when used with Lambda

• Do something if nonNull and something else if Null

• Optional.ofNullable(obj).map(obj -> {
      doSomething(obj)
      return obj;
  }).orElseGet(() -> {
      logForNull();
      return null;
  });
  
  
  Here, If the object is nonNull, then only the value will be applied to the mapping function