Well, this post can be most opinion oriented and every one should learn languages as per their interest, Here are some of the facts. 

World leaders use java: According to google survey, Java is the most searched programming language in the world. Though its origins are similar to C and C++, Java adds some solution to complex problems to the real world. If we go by the trend, most of the service and product based companies like  Netflix, Google, LinkedIn, Amazon, Facebook etc. are using java in their day to day engineering.

Java Developers make good money: According to Payscale.com Entry level java developers have an income of $60,276 per annum. This figure may vary according to company and location. And with years of experience, this figure goes even far beyond $100 000 per annum.

Huge community support: Over the years, java has built a huge community support and you get answer to almost every questions in java communities like Stack Overflow or GitHub. This level of community support is very difficult to achieve for any new languages.

Java is beginner friendly: If you know little bit of C or C++, java will be a piece of cake for you because all the features are similar(with some upgrades). Its object oriented and best thing about object oriented programs is that its easy to learn.

Java has the future: People say there is lots of competition in market for java developers, well, where there will be career, growth and money, there will be competition and java is not loosing its virtue even after 30 years because of its ecosystem.