实体类

public class Sp {String spdm;String spmc;public Sp() {}public Sp(String spdm, String spmc) {this.spdm = spdm;this.spmc = spmc;}public String getSpdm() {return spdm;}public void setSpdm(String spdm) {this.spdm = spdm;}public String getSpmc() {return spmc;}public void setSpmc(String spmc) {this.spmc = spmc;}
}

list

    public static void main(String[] args) {List<Sp> sps=new ArrayList<>();Sp sp1=new Sp("01","商品1");Sp sp2=new Sp("02","商品2");Sp sp3=new Sp("03","商品3");Sp sp4=new Sp("04","商品4");Sp sp5=new Sp("05","商品5");sps.add(sp1);sps.add(sp2);sps.add(sp3);sps.add(sp4);sps.add(sp5);List<String> spdms=sps.stream().map(u->u.getSpdm()).collect(Collectors.toList());System.out.println(spdms);}

结果