Predicate p1=cb.like(root.get(“name”).as(String.class), “%”+uqm.getName()+“%”);Predicate p2=cb.equal(root.get("uuid").as(Integer.class), uqm.getUuid());Predicate p3=cb.gt(root.get("age").as(Integer.class), uqm.getAge());构建组合的Predicate示例：Predicate p = cb.and(p3,cb.or(p1,p2));

//需要查询的对象
public class Qfjbxxdz {@Id@GeneratedValue(generator = "system-uuid")@GenericGenerator(name = "system-uuid", strategy = "uuid.hex")private String id;@OneToOne@JoinColumn(name = "qfjbxx")private Qfjbxx qfjbxx; //关联表private String fzcc;private String fzccName;@ManyToOne@JoinColumn(name = "criminalInfo")private CriminalInfo criminalInfo;//关联表@Column(length=800)private String bz;//get/set......
}//创建构造Specification的方法
//这里我传入两个条件参数因为与前段框架有关，你们写的时候具体自己业务自行决断
private Specification<Qfjbxxdz> getWhereClause(final JSONArray condetion,final JSONArray search) {return new Specification<Qfjbxxdz>() {@Overridepublic Predicate toPredicate(Root<Qfjbxxdz> root, CriteriaQuery<?> query, CriteriaBuilder cb) {List<Predicate> predicate = new ArrayList<>();Iterator<JSONObject> iterator = condetion.iterator();Predicate preP = null;while(iterator.hasNext()){JSONObject jsonObject = iterator.next();//注意：这里用的root.join 因为我们要用qfjbxx对象里的字段作为条件就必须这样做join方法有很多重载，使用的时候可以多根据自己业务决断Predicate p1 = cb.equal(root.join("qfjbxx").get("id").as(String.class),jsonObject.get("fzId").toString());Predicate p2 = cb.equal(root.get("fzcc").as(String.class),jsonObject.get("ccId").toString());if(preP!=null){preP = cb.or(preP,cb.and(p1,p2));}else{preP = cb.and(p1,p2);}}JSONObject jsonSearch=(JSONObject) search.get(0);Predicate p3=null;if(null!=jsonSearch.get("xm")&&jsonSearch.get("xm").toString().length()>0){p3=cb.like(root.join("criminalInfo").get("xm").as(String.class),"%"+jsonSearch.get("xm").toString()+"%");}Predicate p4=null;if(null!=jsonSearch.get("fzmc")&&jsonSearch.get("fzmc").toString().length()>0){p4=cb.like(root.join("qfjbxx").get("fzmc").as(String.class),"%"+jsonSearch.get("fzmc").toString()+"%");}Predicate preA;if(null!=p3&&null!=p4){Predicate  preS =cb.and(p3,p4);preA =cb.and(preP,preS);}else if(null==p3&&null!=p4){preA=cb.and(preP,p4);}else if(null!=p3&&null==p4){preA=cb.and(preP,p3);}else{preA=preP;}predicate.add(preA);Predicate[] pre = new Predicate[predicate.size()];query.where(predicate.toArray(pre));return query.getRestriction();}

studentInfoDao.findAll(new Specification<StudentInfo> () {  public Predicate toPredicate(Root<StudentInfo> root,  CriteriaQuery<?> query, CriteriaBuilder cb) {  Path<String> namePath = root.get("name");  Path<String> nicknamePath = root.get("nickname");  /** * 连接查询条件, 不定参数，可以连接0..N个查询条件 */  query.where(cb.like(namePath, "%李%"), cb.like(nicknamePath, "%王%")); //这里可以设置任意条查询条件  return null;  }  }, page);  }