使用条件实现搜索过滤器 [英] Implement search filter with conditions
问题描述
我想用几个子条件实现搜索功能.我试过这个:
I want to implement search functionality with several sub conditions. I tried this:
@GetMapping("find")
public Page<PaymentTransactionsDTO> getAllBySpecification(
@And({
@Spec(path = "name", spec = LikeIgnoreCase.class),
@Spec(path = "unique_id", spec = LikeIgnoreCase.class),
@Spec(path = "createdAt", params = "from", spec = GreaterThanOrEqual.class),
@Spec(path = "createdAt", params = "to", spec = LessThanOrEqual.class)
}) Specification<PaymentTransactions> specification,
Pageable pageable
) {
return transactionService.getAllBySpecification(specification, pageable));
}
存储库:
@Override
public Page<PaymentTransactions> getAllBySpecification(final Specification<PaymentTransactions> specification, final Pageable pageable) {
return dao.findAll(specification, pageable);
}
目前此请求正在运行:
GET /api/transactions/find?unique_id=22&page=0&size=10
但我还想实现这些额外的搜索条件，不仅发送对 unique_id 的基本搜索:
But also I want to implement these additional search conditions not only sending basic search for unique_id:
start with
=
end with
contains
使用https://github.com/tkaczmarzyk/specification-arg-resolver 有没有办法发送额外的子条件?我通常找不到针对此问题的解决方案，发送这些值的最佳做法是什么?
Using https://github.com/tkaczmarzyk/specification-arg-resolver is there some way to send additional sub conditions? I can't find a solution for this issue in general what are the best practices to send these values?
推荐答案
如果您想创建非常特殊的过滤器，我相信您应该从发明搜索界面开始.例如像这样:
If you want to create your very special filter I believe you should start with invention of your search interface. For example like that:
GET /models?name=eq(john smith)&createdAt=between(2019-01-01,2019-01-31)
GET /models?name=like(sm)&createdAt=from(2019-01-01)
GET /models?name=sw(john)&createdAt=to(2019-01-31)
之后，您将能够尝试实施它.
After that, you will be able to try to implement it.
IMO 解决此类任务的最佳方法是使用 Spring Data JPA 规范(和 JPA Criteria API).例如:
IMO the best way to solve such a task is to use Spring Data JPA Specifications (and JPA Criteria API). For example:
1) 让我们创建一个 Filter 类来为我们的实体 Model 实现Specification:
1) Let's create a Filter class that implements Specification for our entity Model:
@Value
public class ModelFilter implements Specification<Model> {
private String name;
private String createdAt;
@Override
public Predicate toPredicate(Root<Model> root, CriteriaQuery<?> query, CriteriaBuilder builder) {
List<Predicate> predicates = new ArrayList<>();
// Prepare predicates and fill the list with them...
return builder.and(predicates.toArray(new Predicate[0]));
}
}
2) 然后创建一个控制器方法:
2) Then create a controller method:
@GetMapping
public List<Model> getAllByFilter(ModelFilter filter) {
return repo.findAll(filter);
}
剩下要做的就是准备我们的谓词 ))
All that's left to do is prepare our predicates ))
为此，我们可以先创建一个方便的Predicate Builder"界面:
To make this, we can create a handy 'Predicate Builder' interface first:
@FunctionalInterface
interface PredicateBuilder<T> {
Optional<Predicate> get(String fieldName, String value, Root<T> root, CriteriaBuilder builder);
static Matcher getMatcher(String op, String value) {
return getMatcher(op, value, "(.+)");
}
static Matcher getMatcher(String op, String value, String pattern) {
return Pattern.compile(op + "\(" + pattern + "\)").matcher(value);
}
}
然后尝试制作我们的谓词:
Then try to make our predicates:
相等
PredicateBuilder<Model> eq = (fieldName, value, root, cb) -> {
Matcher m = getMatcher("eq", value);
if (m.matches()) {
return Optional.of(cb.equal(cb.upper(root.get(fieldName)), m.group(1).toUpperCase()));
} else {
return Optional.empty();
}
};
喜欢
PredicateBuilder<Model> like = (fn, value, root, cb) -> {
Matcher m = getMatcher("like", value);
if (m.matches()) {
return Optional.of(cb.like(cb.upper(root.get(fn)), "%" + m.group(1).toUpperCase() + "%"));
} else {
return Optional.empty();
}
};
开始于
PredicateBuilder<Model> sw = (fn, value, root, cb) -> {
Matcher m = getMatcher("sw", value);
if (m.matches()) {
return Optional.of(cb.like(cb.upper(root.get(fn)), m.group(1).toUpperCase() + "%"));
} else {
return Optional.empty();
}
};
之间
PredicateBuilder<Model> between = (fn, value, root, cb) -> {
Matcher m = getMatcher("between", value, "(.+)\s*,\s*(.+)");
if (m.matches()) {
LocalDate from = LocalDate.parse(m.group(1));
LocalDate to = LocalDate.parse(m.group(2));
return Optional.of(cb.between(root.get(fn), from, to));
} else {
return Optional.empty();
}
};
来自
PredicateBuilder<Model> from = (fn, value, root, cb) -> {
Matcher m = getMatcher("from", value);
if (m.matches()) {
LocalDate from = LocalDate.parse(m.group(1));
return Optional.of(cb.greaterThanOrEqualTo(root.get(fn), from));
} else {
return Optional.empty();
}
};
到
PredicateBuilder<Model> to = (fn, value, root, cb) -> {
Matcher m = getMatcher("to", value);
if (m.matches()) {
LocalDate to = LocalDate.parse(m.group(1));
return Optional.of(cb.lessThanOrEqualTo(root.get(fn), to));
} else {
return Optional.empty();
}
};
剩下的只是完成Filter类:
@Value
public class ModelFilter implements Specification<Model> {
private String name;
private String createdAt;
PredicateBuilder<Model> eq = ... ;
PredicateBuilder<Model> like = ... ;
PredicateBuilder<Model> sw = ... ;
PredicateBuilder<Model> between = ... ;
PredicateBuilder<Model> from = ... ;
PredicateBuilder<Model> to = ... ;
@Override
public Predicate toPredicate(Root<Model> root, CriteriaQuery<?> query, CriteriaBuilder builder) {
List<Predicate> predicates = new ArrayList<>();
if (name != null) {
eq.get("name", name, root, builder).ifPresent(predicates::add);
like.get("name", name, root, builder).ifPresent(predicates::add);
sw.get("name", name, root, builder).ifPresent(predicates::add);
}
if (createdAt != null) {
between.get("createdAt", createdAt, root, builder).ifPresent(predicates::add);
from.get("createdAt", createdAt, root, builder).ifPresent(predicates::add);
to.get("createdAt", createdAt, root, builder).ifPresent(predicates::add);
}
return builder.and(predicates.toArray(new Predicate[0]));
}
}
当然，这只是实现的一个例子.您可以创建自己需要的规范和谓词的实现.这里的主要内容是:
Of course it's just one example of implementation. You can create your very own implementation of specifications and predicates you need. The main things here are:
- 想出你的搜索界面
- 制定您的过滤器"规范
- 准备您需要的所有谓词
- 在您的控制器方法中使用过滤器规范
这篇关于使用条件实现搜索过滤器的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
