Generally speaking, the cost of Java training courses varies with training institutions, course quality, learning time and other factors. In Beijing, the cost of Java training courses is generally between 10000-30000, and the learning time is generally about 3 to 6 months.

Specifically, some well-known training institutions may charge higher fees, but the course quality and teachers are relatively better. Some small training institutions or online training institutions may charge relatively low fees, but the teaching quality and learning effect may be different.

In addition, different Java training courses will set different fees according to the course content and difficulty. For example, some training institutions will provide more advanced courses, including framework, database, Web development, etc., and the cost may be higher. And some basic courses are relatively cheap.

In addition, the cost of learning a four-month Java training course varies according to the specific situation. Some training institutions may provide more comprehensive courses, including more practical projects and course materials, and these costs may be higher. And some simple courses may be relatively cheaper.

In a word, if you want to know the specific cost, I suggest you consult several training institutions to learn about their curriculum, teaching staff, learning effect and other information, so that you can make a better choice. At the same time, we should also pay attention not to be confused by advertisements, and make judgments and choices according to our actual situation.