Spring数据规范-带连接的RSQL

Question

我正在尝试开发一个具有规范和RSQL的搜索API。遵循本教程-https://www.baeldung.com/rest-api-search-language-rsql-fiql

@Entity
public class User{

    @Column(nullable = false)
    private String firstName;

    @OneToOne(targetEntity = UserProfile.class, fetch = FetchType.EAGER)
    @JoinColumn(nullable = false, name = "user_profile_id")
    private UserProfile userProfile;
...

@Entity
public class UserProfile{

    @Column(nullable = false)
    private String education;

    ...

@Override
public Predicate toPredicate(Root<T> root, CriteriaQuery<?> query, CriteriaBuilder builder) {
    List<Object> args = castArguments(root);
    Object argument = args.get(0);

    switch (RsqlSearchOperation.getSimpleOperator(operator)) {

    case EQUAL: {
            if (argument instanceof String) {               
                return builder.like(root.get(property), argument.toString().replace('*', '%'));
            } else if (argument == null) {
                return builder.isNull(root.get(property));
            } else {
                return builder.equal(root.get(property), argument);
            }
        }
        case NOT_EQUAL: {

if (argument instanceof String) {
                Join<User, UserProfile> profileJoin = root.join("user_profile_id");

                return builder.like(root.get(property), profileJoin.get(property));
            } else if (argument == null) {

Answer 1

看来没有通用的具体解决方案。所以我做了它，这几乎是通用的。

switch (RsqlSearchOperation.getSimpleOperator(operator)) {

        case EQUAL: {
            if (doesClassContainProperty(UserProfile.class, property)) {
                Join<User, UserProfile> profileJoin = root.join("user_profile_id");
                return builder.equal(profileJoin.get(property), argument);
            } else {
                return builder.equal(root.get(property), argument);
            }
        }

下面是检查传递的参数是在根类中还是在联接类中的方法

public boolean doesClassContainProperty(Class<?> genericClass, String fieldName) {
        return Arrays.stream(genericClass.getDeclaredFields()).anyMatch(f -> f.getName().equals(fieldName));
    }