Skip to content

Commit

Permalink
Polishing.
Browse files Browse the repository at this point in the history 
Fix version reference to Spring Data Commons. Avoid stream creation when fetching all/one/first element. Move off deprecated API. Add override comments. Add null guargs.

See #2294
Original pull request: #2326.
  • Loading branch information
@mp911de
mp911de committed Oct 8, 2021
1 parent ea430f3 commit a31c39d
Show file tree
Hide file tree
Showing 5 changed files with 162 additions and 42 deletions.
2 changes: 1 addition & 1 deletion pom.xml
View file
Original file line number Diff line number Diff line change
Expand Up @@ -25,7 +25,7 @@
<hibernate>5.5.3.Final</hibernate>
<mysql-connector-java>8.0.23</mysql-connector-java>
<postgresql>42.2.19</postgresql>
<springdata.commons>2.6.0-2228-SNAPSHOT</springdata.commons>
<springdata.commons>2.6.0-SNAPSHOT</springdata.commons>
<vavr>0.10.3</vavr>

<hibernate.groupId>org.hibernate</hibernate.groupId>
Expand Down
93 changes: 74 additions & 19 deletions ...n/java/org/springframework/data/jpa/repository/support/FetchableFluentQueryByExample.java
View file
Original file line number Diff line number Diff line change
Expand Up @@ -15,10 +15,10 @@
*/
package org.springframework.data.jpa.repository.support;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.function.Function;
import java.util.stream.Collectors;
import java.util.stream.Stream;

import javax.persistence.EntityManager;
Expand All @@ -37,6 +37,7 @@
import org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery;
import org.springframework.data.support.PageableExecutionUtils;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;

/**
* Immutable implementation of {@link FetchableFluentQuery} based on Query by {@link Example}. All methods that return a
Expand All @@ -45,6 +46,7 @@
* @param <S> Domain type
* @param <R> Result type
* @author Greg Turnquist
* @author Mark Paluch
* @since 2.6
*/
class FetchableFluentQueryByExample<S, R> extends FluentQuerySupport<R> implements FetchableFluentQuery<R> {
Expand Down Expand Up @@ -79,87 +81,126 @@ private FetchableFluentQueryByExample(Example<S> example, Class<R> returnType, S
this.escapeCharacter = escapeCharacter;
}

/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery#sortBy(org.springframework.data.domain.Sort)
*/
@Override
public FetchableFluentQuery<R> sortBy(Sort sort) {

return new FetchableFluentQueryByExample<S, R>(this.example, this.resultType, this.sort.and(sort), this.properties,
Assert.notNull(sort, "Sort must not be null!");

return new FetchableFluentQueryByExample<>(this.example, this.resultType, this.sort.and(sort), this.properties,
this.finder, this.countOperation, this.existsOperation, this.context, this.entityManager, this.escapeCharacter);
}

/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery#as(java.lang.Class)
*/
@Override
public <NR> FetchableFluentQuery<NR> as(Class<NR> resultType) {

Assert.notNull(resultType, "Projection target type must not be null!");
if (!resultType.isInterface()) {
throw new UnsupportedOperationException("Class-based DTOs are not yet supported.");
}

return new FetchableFluentQueryByExample<S, NR>(this.example, resultType, this.sort, this.properties, this.finder,
return new FetchableFluentQueryByExample<>(this.example, resultType, this.sort, this.properties, this.finder,
this.countOperation, this.existsOperation, this.context, this.entityManager, this.escapeCharacter);
}

/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery#project(java.util.Collection)
*/
@Override
public FetchableFluentQuery<R> project(Collection<String> properties) {

return new FetchableFluentQueryByExample<>(this.example, this.resultType, this.sort, mergeProperties(properties),
this.finder, this.countOperation, this.existsOperation, this.context, this.entityManager, this.escapeCharacter);
}

/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery#oneValue()
*/
@Override
public R oneValue() {

TypedQuery<S> limitedQuery = this.finder.apply(this.sort);
limitedQuery.setMaxResults(2); // Never need more than 2 values

List<R> results = limitedQuery //
.getResultStream() //
.map(getConversionFunction(this.example.getProbeType(), this.resultType)) //
.collect(Collectors.toList());
;
List<S> results = limitedQuery.getResultList();

if (results.size() > 1) {
throw new IncorrectResultSizeDataAccessException(1);
}

return results.isEmpty() ? null : results.get(0);
return results.isEmpty() ? null : getConversionFunction().apply(results.get(0));
}

/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery#firstValue()
*/
@Override
public R firstValue() {

TypedQuery<S> limitedQuery = this.finder.apply(this.sort);
limitedQuery.setMaxResults(1); // Never need more than 1 value

List<R> results = limitedQuery //
.getResultStream() //
.map(getConversionFunction(this.example.getProbeType(), this.resultType)) //
.collect(Collectors.toList());
List<S> results = limitedQuery.getResultList();

return results.isEmpty() ? null : results.get(0);
return results.isEmpty() ? null : getConversionFunction().apply(results.get(0));
}

/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery#all()
*/
@Override
public List<R> all() {
return stream().collect(Collectors.toList());

List<S> resultList = this.finder.apply(this.sort).getResultList();

return convert(resultList);
}

/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery#page(org.springframework.data.domain.Pageable)
*/
@Override
public Page<R> page(Pageable pageable) {
return pageable.isUnpaged() ? new PageImpl<>(all()) : readPage(pageable);
}

/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery#stream()
*/
@Override
public Stream<R> stream() {

return this.finder.apply(this.sort) //
.getResultStream() //
.map(getConversionFunction(this.example.getProbeType(), this.resultType));
.map(getConversionFunction());
}

/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery#count()
*/
@Override
public long count() {
return this.countOperation.apply(example);
}

/*
* (non-Javadoc)
* @see org.springframework.data.repository.query.FluentQuery.FetchableFluentQuery#exists()
*/
@Override
public boolean exists() {
return this.existsOperation.apply(example);
Expand All @@ -174,10 +215,24 @@ private Page<R> readPage(Pageable pageable) {
pagedQuery.setMaxResults(pageable.getPageSize());
}

List<R> paginatedResults = pagedQuery.getResultStream() //
.map(getConversionFunction(this.example.getProbeType(), this.resultType)) //
.collect(Collectors.toList());
List<R> paginatedResults = convert(pagedQuery.getResultList());

return PageableExecutionUtils.getPage(paginatedResults, pageable, () -> this.countOperation.apply(this.example));
}

private List<R> convert(List<S> resultList) {

Function<Object, R> conversionFunction = getConversionFunction();
List<R> mapped = new ArrayList<>(resultList.size());

for (S s : resultList) {
mapped.add(conversionFunction.apply(s));
}
return mapped;
}

private Function<Object, R> getConversionFunction() {
return getConversionFunction(this.example.getProbeType(), this.resultType);
}

}
Loading

0 comments on commit a31c39d

Please sign in to comment.