Java读取txt文件中的第一个单词，并在一行中编辑多个字符串*

I have a problem that needs help. My code (below) is a program that helps you with a crossword. It finds all possible solutions from dictionary. If I work with test.txt, you put a stream in for example t*e* and the program works and returns tree and tret. Below you can see my test.txt example. However, I need to make this program to work with a dictionary which contains over 100000 words. Dictionary.txt as shown bellow has 4 words or numbers in 1 row. Any ideas how to read only first word in each line. I would not like a full solution, just some options on how to accomplish this.I have a problem that needs help. My code (belo