Demo02_getStream.java 1.4 KB

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  1. package J20250724.demo02_function_program;
  2. import java.util.*;
  3. import java.util.stream.Stream;
  4. /**
  5. * @author WanJl
  6. * @version 1.0
  7. * @title Demo02_getSream
  8. * @description
  9. * @create 2025/7/24
  10. */
  11. public class Demo02_getStream {
  12. public static void main(String[] args) {
  13. //Collection体系的集合
  14. List<String> list=new ArrayList<>();
  15. Stream<String> listStream = list.stream();
  16. Set<String> set=new HashSet<>();
  17. Stream<String> setStream = set.stream();
  18. //Map体系集合
  19. Map<String ,Integer> map=new HashMap<>();
  20. //把所有的key生成流
  21. Stream<String> keyStream = map.keySet().stream();
  22. //把所有的value生成流
  23. Stream<Integer> valueStream = map.values().stream();
  24. //把所有的键值对对象生成流
  25. Stream<Map.Entry<String, Integer>> entryStream = map.entrySet().stream();
  26. //数组
  27. String[] strArray={"hello","world","java","lambda","stream"};
  28. Stream<String> arrayStream = Arrays.stream(strArray);
  29. //同种数据类型的多个数据
  30. Student s1=new Student(1,"张三");
  31. Student s2=new Student(1,"张三");
  32. Student s3=new Student(1,"张三");
  33. Student s4=new Student(1,"张三");
  34. Stream<Student> objectStream = Stream.of(s1, s2, s3, s4);
  35. Stream<Integer> integerStream = Stream.of(1, 2, 3, 4, 6, 78, 1, 658);
  36. }
  37. }