使用java8流的规范组合列表

使用java8流的规范组合列表,java,spring-boot,java-8,spring-data-jpa,Java,Spring Boot,Java 8,Spring Data Jpa,如何在此代码中使用Java8流: Specification<T> specification = specifications.getSpec(searchCriteria.getConditions().get(0)); for(int i = 1; i < searchCriteria.getConditions().size(); i++) { specification = specification.and(getSpec(s

如何在此代码中使用Java8流:

Specification<T> specification = specifications.getSpec(searchCriteria.getConditions().get(0));
        for(int i = 1; i < searchCriteria.getConditions().size(); i++) {
            specification = specification.and(getSpec(searchCriteria.getConditions().get(i)));
    }
相关类和方法:

@Getter
@Setter
public class SearchCriteria implements Serializable{

    private static final long serialVersionUID = 1L;

    private List<Condition> conditions;
    private Integer limit;
    private Integer offset;

    @Getter
    @Setter
    public class Condition{
        private String key;
        private EConstant.OPERATION operation;
        private String value;
    }
}
public Specification<T> getSpec(SearchCriteria.Condition condition){
....
}
@Getter
@塞特
公共类SearchCriteria实现可序列化{
私有静态最终长serialVersionUID=1L;
私人名单条件;
私有整数限制;
专用整数偏移量;
@吸气剂
@塞特
公共阶级状况{
私钥;
私人经济运行;
私有字符串值;
}
}
公共规范getSpec(SearchCriteria.Condition){
....
}

如果我理解正确:

 IntStream.range(0, searchCriteria.getConditions().size())
         .mapToObj(index-> getSpec(searchCriteria.getConditions().get(index)))
         .reduce(Specification::and)
         .orElseThrow(SomeException::new) // or any default from Specification...
或者更好:

 searchCriteria.getConditions()
               .stream()
               .map(this::getSpec)
               .reduce(Specification::and)
               .orElseThrow(SomeException::new)
 searchCriteria.getConditions()
               .stream()
               .map(this::getSpec)
               .reduce(Specification::and)
               .orElseThrow(SomeException::new)