title: eclipse can not import some class automatically
body: <p>I have a spring-boot(maven) project and I have added the spring-security dependency into the pom.xml. When I am coding it cannot import some class about security automatically as the picture shows. I have to import the class by typing the full path, but I can not know all the class's full path. As the second picture shows I have to type the Highlight's code when I want to use some class. I cannot use ctrl + shift + O to import it. I have updated my dependency 
  There is no problem in it. </p>
  
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