From 14db73cf021d2d94de3d6617387648732f34b08e Mon Sep 17 00:00:00 2001 From: amit2103 Date: Sat, 27 Oct 2018 21:10:33 +0530 Subject: [PATCH] [BAEL-9557] - Migrated the spring-rest-query-language to Java 8 idioms --- .../dao/MyUserPredicatesBuilder.java | 50 ++++++++++++------- .../org/baeldung/persistence/dao/UserDAO.java | 26 +++------- .../dao/UserSearchQueryCriteriaConsumer.java | 43 ++++++++++++++++ .../dao/UserSpecificationsBuilder.java | 17 ++++--- .../dao/rsql/GenericRsqlSpecBuilder.java | 49 +++++++++--------- .../dao/rsql/GenericRsqlSpecification.java | 29 +++++++---- .../web/controller/UserController.java | 5 +- .../org/baeldung/web/util/CriteriaParser.java | 5 +- 8 files changed, 142 insertions(+), 82 deletions(-) create mode 100644 spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserSearchQueryCriteriaConsumer.java diff --git a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/MyUserPredicatesBuilder.java b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/MyUserPredicatesBuilder.java index c7b9f8358e..4f181b9c4c 100644 --- a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/MyUserPredicatesBuilder.java +++ b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/MyUserPredicatesBuilder.java @@ -1,10 +1,13 @@ package org.baeldung.persistence.dao; -import com.querydsl.core.types.dsl.BooleanExpression; -import org.baeldung.web.util.SearchCriteria; - import java.util.ArrayList; import java.util.List; +import java.util.stream.Collectors; + +import org.baeldung.web.util.SearchCriteria; + +import com.querydsl.core.types.dsl.BooleanExpression; +import com.querydsl.core.types.dsl.Expressions; public final class MyUserPredicatesBuilder { private final List params; @@ -22,21 +25,34 @@ public final class MyUserPredicatesBuilder { if (params.size() == 0) { return null; } - - final List predicates = new ArrayList<>(); - MyUserPredicate predicate; - for (final SearchCriteria param : params) { - predicate = new MyUserPredicate(param); - final BooleanExpression exp = predicate.getPredicate(); - if (exp != null) { - predicates.add(exp); - } - } - - BooleanExpression result = predicates.get(0); - for (int i = 1; i < predicates.size(); i++) { - result = result.and(predicates.get(i)); + + final List predicates = params.stream().map(param -> { + MyUserPredicate predicate = new MyUserPredicate(param); + return predicate.getPredicate(); + }).filter(predicate -> predicate != null).collect(Collectors.toCollection(ArrayList::new)); + + BooleanExpression result = Expressions.asBoolean(true).isTrue(); + for (BooleanExpression predicate : predicates) { + result = result.and(predicate); } + return result; } + + static class BooleanExpressionWrapper { + + private BooleanExpression result; + + public BooleanExpressionWrapper(final BooleanExpression result) { + super(); + this.result = result; + } + + public BooleanExpression getResult() { + return result; + } + public void setResult(BooleanExpression result) { + this.result = result; + } + } } diff --git a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserDAO.java b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserDAO.java index 8a01f8c97c..4f2f6003e4 100644 --- a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserDAO.java +++ b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserDAO.java @@ -1,8 +1,6 @@ package org.baeldung.persistence.dao; -import org.baeldung.persistence.model.User; -import org.baeldung.web.util.SearchCriteria; -import org.springframework.stereotype.Repository; +import java.util.List; import javax.persistence.EntityManager; import javax.persistence.PersistenceContext; @@ -10,7 +8,10 @@ import javax.persistence.criteria.CriteriaBuilder; import javax.persistence.criteria.CriteriaQuery; import javax.persistence.criteria.Predicate; import javax.persistence.criteria.Root; -import java.util.List; + +import org.baeldung.persistence.model.User; +import org.baeldung.web.util.SearchCriteria; +import org.springframework.stereotype.Repository; @Repository public class UserDAO implements IUserDAO { @@ -25,20 +26,9 @@ public class UserDAO implements IUserDAO { final Root r = query.from(User.class); Predicate predicate = builder.conjunction(); - - for (final SearchCriteria param : params) { - if (param.getOperation().equalsIgnoreCase(">")) { - predicate = builder.and(predicate, builder.greaterThanOrEqualTo(r.get(param.getKey()), param.getValue().toString())); - } else if (param.getOperation().equalsIgnoreCase("<")) { - predicate = builder.and(predicate, builder.lessThanOrEqualTo(r.get(param.getKey()), param.getValue().toString())); - } else if (param.getOperation().equalsIgnoreCase(":")) { - if (r.get(param.getKey()).getJavaType() == String.class) { - predicate = builder.and(predicate, builder.like(r.get(param.getKey()), "%" + param.getValue() + "%")); - } else { - predicate = builder.and(predicate, builder.equal(r.get(param.getKey()), param.getValue())); - } - } - } + UserSearchQueryCriteriaConsumer searchConsumer = new UserSearchQueryCriteriaConsumer(predicate, builder, r); + params.stream().forEach(searchConsumer); + predicate = searchConsumer.getPredicate(); query.where(predicate); return entityManager.createQuery(query).getResultList(); diff --git a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserSearchQueryCriteriaConsumer.java b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserSearchQueryCriteriaConsumer.java new file mode 100644 index 0000000000..8b15ef1605 --- /dev/null +++ b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserSearchQueryCriteriaConsumer.java @@ -0,0 +1,43 @@ +package org.baeldung.persistence.dao; + +import java.util.function.Consumer; + +import javax.persistence.criteria.CriteriaBuilder; +import javax.persistence.criteria.Predicate; +import javax.persistence.criteria.Root; + +import org.baeldung.web.util.SearchCriteria; + +public class UserSearchQueryCriteriaConsumer implements Consumer{ + + private Predicate predicate; + private CriteriaBuilder builder; + private Root r; + + public UserSearchQueryCriteriaConsumer(Predicate predicate, CriteriaBuilder builder, Root r) { + super(); + this.predicate = predicate; + this.builder = builder; + this.r= r; + } + + @Override + public void accept(SearchCriteria param) { + + if (param.getOperation().equalsIgnoreCase(">")) { + predicate = builder.and(predicate, builder.greaterThanOrEqualTo(r.get(param.getKey()), param.getValue().toString())); + } else if (param.getOperation().equalsIgnoreCase("<")) { + predicate = builder.and(predicate, builder.lessThanOrEqualTo(r.get(param.getKey()), param.getValue().toString())); + } else if (param.getOperation().equalsIgnoreCase(":")) { + if (r.get(param.getKey()).getJavaType() == String.class) { + predicate = builder.and(predicate, builder.like(r.get(param.getKey()), "%" + param.getValue() + "%")); + } else { + predicate = builder.and(predicate, builder.equal(r.get(param.getKey()), param.getValue())); + } + } + } + + public Predicate getPredicate() { + return predicate; + } +} \ No newline at end of file diff --git a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserSpecificationsBuilder.java b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserSpecificationsBuilder.java index 918e77720f..cb8918b807 100644 --- a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserSpecificationsBuilder.java +++ b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/UserSpecificationsBuilder.java @@ -1,14 +1,15 @@ package org.baeldung.persistence.dao; +import java.util.ArrayList; +import java.util.List; +import java.util.stream.Collectors; + import org.baeldung.persistence.model.User; import org.baeldung.web.util.SearchOperation; import org.baeldung.web.util.SpecSearchCriteria; import org.springframework.data.jpa.domain.Specification; import org.springframework.data.jpa.domain.Specifications; -import java.util.ArrayList; -import java.util.List; - public final class UserSpecificationsBuilder { private final List params; @@ -48,15 +49,19 @@ public final class UserSpecificationsBuilder { if (params.size() == 0) return null; - Specification result = new UserSpecification(params.get(0)); + final List> specs = params.stream() + .map(UserSpecification::new) + .collect(Collectors.toCollection(ArrayList::new)); + + Specification result = specs.get(0); for (int i = 1; i < params.size(); i++) { result = params.get(i) .isOrPredicate() ? Specifications.where(result) - .or(new UserSpecification(params.get(i))) + .or(specs.get(i)) : Specifications.where(result) - .and(new UserSpecification(params.get(i))); + .and(specs.get(i)); } diff --git a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/rsql/GenericRsqlSpecBuilder.java b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/rsql/GenericRsqlSpecBuilder.java index 4efec00ed6..3076300c36 100644 --- a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/rsql/GenericRsqlSpecBuilder.java +++ b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/rsql/GenericRsqlSpecBuilder.java @@ -1,13 +1,15 @@ package org.baeldung.persistence.dao.rsql; +import java.util.ArrayList; +import java.util.List; +import java.util.stream.Collectors; + +import org.springframework.data.jpa.domain.Specifications; + import cz.jirutka.rsql.parser.ast.ComparisonNode; import cz.jirutka.rsql.parser.ast.LogicalNode; import cz.jirutka.rsql.parser.ast.LogicalOperator; import cz.jirutka.rsql.parser.ast.Node; -import org.springframework.data.jpa.domain.Specifications; - -import java.util.ArrayList; -import java.util.List; public class GenericRsqlSpecBuilder { @@ -22,29 +24,24 @@ public class GenericRsqlSpecBuilder { } public Specifications createSpecification(final LogicalNode logicalNode) { - final List> specs = new ArrayList>(); - Specifications temp; - for (final Node node : logicalNode.getChildren()) { - temp = createSpecification(node); - if (temp != null) { - specs.add(temp); + + List> specs = logicalNode.getChildren() + .stream() + .map(node -> createSpecification(node)) + .filter(specifications -> specifications != null) + .collect(Collectors.toCollection(ArrayList::new)); + + Specifications initialSpec = specs.stream().findFirst().get(); + + Specifications result = specs.stream().skip(1).reduce(initialSpec, (firstSpec, secondSpec) -> { + if (logicalNode.getOperator() == LogicalOperator.AND) { + return Specifications.where(firstSpec).and(secondSpec); + } else if (logicalNode.getOperator() == LogicalOperator.OR) { + return Specifications.where(firstSpec).or(secondSpec); } - } - - Specifications result = specs.get(0); - - if (logicalNode.getOperator() == LogicalOperator.AND) { - for (int i = 1; i < specs.size(); i++) { - result = Specifications.where(result).and(specs.get(i)); - } - } - - else if (logicalNode.getOperator() == LogicalOperator.OR) { - for (int i = 1; i < specs.size(); i++) { - result = Specifications.where(result).or(specs.get(i)); - } - } - + return firstSpec; + }); + return result; } diff --git a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/rsql/GenericRsqlSpecification.java b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/rsql/GenericRsqlSpecification.java index 937c6d953c..3e99208684 100644 --- a/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/rsql/GenericRsqlSpecification.java +++ b/spring-rest-query-language/src/main/java/org/baeldung/persistence/dao/rsql/GenericRsqlSpecification.java @@ -1,14 +1,17 @@ package org.baeldung.persistence.dao.rsql; -import cz.jirutka.rsql.parser.ast.ComparisonOperator; -import org.springframework.data.jpa.domain.Specification; +import java.util.ArrayList; +import java.util.List; +import java.util.stream.Collectors; import javax.persistence.criteria.CriteriaBuilder; import javax.persistence.criteria.CriteriaQuery; import javax.persistence.criteria.Predicate; import javax.persistence.criteria.Root; -import java.util.ArrayList; -import java.util.List; + +import org.springframework.data.jpa.domain.Specification; + +import cz.jirutka.rsql.parser.ast.ComparisonOperator; public class GenericRsqlSpecification implements Specification { @@ -71,18 +74,22 @@ public class GenericRsqlSpecification implements Specification { // === private private List castArguments(final Root root) { - final List args = new ArrayList(); + final Class type = root.get(property).getJavaType(); - - for (final String argument : arguments) { + + final List args = arguments.stream().map(arg -> { + + Object obj; if (type.equals(Integer.class)) { - args.add(Integer.parseInt(argument)); + obj = Integer.parseInt(arg); } else if (type.equals(Long.class)) { - args.add(Long.parseLong(argument)); + obj = Long.parseLong(arg); } else { - args.add(argument); + obj = arg; } - } + return obj; + + }).collect(Collectors.toCollection(ArrayList::new)); return args; } diff --git a/spring-rest-query-language/src/main/java/org/baeldung/web/controller/UserController.java b/spring-rest-query-language/src/main/java/org/baeldung/web/controller/UserController.java index 8953a52a1b..13f986eb20 100644 --- a/spring-rest-query-language/src/main/java/org/baeldung/web/controller/UserController.java +++ b/spring-rest-query-language/src/main/java/org/baeldung/web/controller/UserController.java @@ -2,6 +2,7 @@ package org.baeldung.web.controller; import java.util.ArrayList; import java.util.List; +import java.util.Optional; import java.util.regex.Matcher; import java.util.regex.Pattern; @@ -63,7 +64,7 @@ public class UserController { @ResponseBody public List findAll(@RequestParam(value = "search", required = false) String search) { List params = new ArrayList(); - if (search != null) { + if (Optional.ofNullable(search).isPresent()) { Pattern pattern = Pattern.compile("(\\w+?)(:|<|>)(\\w+?),"); Matcher matcher = pattern.matcher(search + ","); while (matcher.find()) { @@ -126,7 +127,7 @@ public class UserController { @ResponseBody public Iterable findAllByQuerydsl(@RequestParam(value = "search") String search) { MyUserPredicatesBuilder builder = new MyUserPredicatesBuilder(); - if (search != null) { + if (Optional.ofNullable(search).isPresent()) { Pattern pattern = Pattern.compile("(\\w+?)(:|<|>)(\\w+?),"); Matcher matcher = pattern.matcher(search + ","); while (matcher.find()) { diff --git a/spring-rest-query-language/src/main/java/org/baeldung/web/util/CriteriaParser.java b/spring-rest-query-language/src/main/java/org/baeldung/web/util/CriteriaParser.java index eabc938bce..a72d07f440 100644 --- a/spring-rest-query-language/src/main/java/org/baeldung/web/util/CriteriaParser.java +++ b/spring-rest-query-language/src/main/java/org/baeldung/web/util/CriteriaParser.java @@ -1,5 +1,6 @@ package org.baeldung.web.util; +import java.util.Arrays; import java.util.Collections; import java.util.Deque; import java.util.HashMap; @@ -45,7 +46,7 @@ public class CriteriaParser { Deque output = new LinkedList<>(); Deque stack = new LinkedList<>(); - for (String token : searchParam.split("\\s+")) { + Arrays.stream(searchParam.split("\\s+")).forEach(token -> { if (ops.containsKey(token)) { while (!stack.isEmpty() && isHigerPrecedenceOperator(token, stack.peek())) output.push(stack.pop() @@ -65,7 +66,7 @@ public class CriteriaParser { output.push(new SpecSearchCriteria(matcher.group(1), matcher.group(2), matcher.group(3), matcher.group(4), matcher.group(5))); } } - } + }); while (!stack.isEmpty()) output.push(stack.pop());