Skip to content

Commit

Permalink
#2313 Make the fetch class immutable
Browse files Browse the repository at this point in the history 
It had already been effectively immutable due to the use of method
`copy` but still used mutable data structures for internal state, which
was not a strong invariant.
  • Loading branch information
@homedirectory
homedirectory committed Oct 3, 2024
1 parent 6bed0d1 commit a691ecd
Showing 1 changed file with 132 additions and 72 deletions.
204 changes: 132 additions & 72 deletions platform-pojo-bl/src/main/java/ua/com/fielden/platform/entity/query/fluent/fetch.java
View file
Original file line number Diff line number Diff line change
@@ -1,27 +1,37 @@
package ua.com.fielden.platform.entity.query.fluent;

import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import ua.com.fielden.platform.entity.AbstractEntity;
import ua.com.fielden.platform.entity.fetch.IFetchProvider;
import ua.com.fielden.platform.entity.query.EntityAggregates;
import ua.com.fielden.platform.entity.query.exceptions.EqlException;
import ua.com.fielden.platform.utils.CollectionUtil;
import ua.com.fielden.platform.utils.ImmutableMapUtils;

import java.util.Map;
import java.util.Objects;
import java.util.Set;

import static java.lang.String.format;
import static java.util.Collections.unmodifiableMap;
import static java.util.Collections.unmodifiableSet;
import static ua.com.fielden.platform.entity.AbstractEntity.ID;
import static ua.com.fielden.platform.entity.AbstractEntity.VERSION;
import static ua.com.fielden.platform.entity.query.fluent.fetch.FetchCategory.ALL;
import static ua.com.fielden.platform.entity.query.fluent.fetch.FetchCategory.DEFAULT;
import static ua.com.fielden.platform.entity.query.fluent.fetch.FetchCategory.ID_AND_VERSION;
import static ua.com.fielden.platform.entity.query.fluent.fetch.FetchCategory.ID_ONLY;
import static ua.com.fielden.platform.entity.query.fluent.fetch.FetchCategory.KEY_AND_DESC;
import static ua.com.fielden.platform.entity.query.fluent.fetch.FetchCategory.*;
import static ua.com.fielden.platform.reflection.Finder.isPropertyPresent;
import static ua.com.fielden.platform.reflection.PropertyTypeDeterminator.determinePropertyType;

import java.util.*;

import ua.com.fielden.platform.entity.AbstractEntity;
import ua.com.fielden.platform.entity.query.EntityAggregates;
import ua.com.fielden.platform.entity.query.exceptions.EqlException;
import ua.com.fielden.platform.utils.CollectionUtil;
import static ua.com.fielden.platform.utils.ImmutableCollectionUtil.concatSet;
import static ua.com.fielden.platform.utils.ImmutableCollectionUtil.setAppend;

/**
* Represents an entity graph that describes the shape of an entity to be fetched.
* <p>
* This class provides a fluent API to build fetch models.
* Methods {@link #with(CharSequence)}, {@link #without(CharSequence)} and their corresponding overloads return a new fetch model instance.
* This representation is <b>immutable</b>.
* <p>
* Unlike {@link IFetchProvider}, this class <b>does not support dot-expression in property paths</b>, only simple property names are allowed.
* To specify a fetch model for a sub-property, use {@link #with(CharSequence, fetch)}.
*
* @param <T> entity type
* @see FetchCategory
Expand Down Expand Up @@ -92,12 +102,27 @@ public enum FetchCategory {
}

private final Class<T> entityType;
private final Map<String, fetch<? extends AbstractEntity<?>>> includedPropsWithModels = new HashMap<>();
private final Set<String> includedProps = new HashSet<>();
private final Set<String> excludedProps = new HashSet<>();
private final Map<String, fetch<? extends AbstractEntity<?>>> includedPropsWithModels;
private final Set<String> includedProps;
private final Set<String> excludedProps;
private final FetchCategory fetchCategory;
private final boolean instrumented;

private fetch(final Class<T> entityType,
final FetchCategory fetchCategory,
final boolean instrumented,
final Map<String, fetch<? extends AbstractEntity<?>>> includedPropsWithModels,
final Set<String> includedProps,
final Set<String> excludedProps)
{
this.entityType = entityType;
this.fetchCategory = fetchCategory;
this.instrumented = instrumented;
this.includedPropsWithModels = includedPropsWithModels;
this.includedProps = includedProps;
this.excludedProps = excludedProps;
}

/**
* Used mainly for serialisation.
*/
Expand All @@ -106,9 +131,7 @@ protected fetch() {
}

public fetch(final Class<T> entityType, final FetchCategory fetchCategory, final boolean instrumented) {
this.entityType = entityType;
this.fetchCategory = fetchCategory;
this.instrumented = instrumented;
this(entityType, fetchCategory, instrumented, ImmutableMap.of(), ImmutableSet.of(), ImmutableSet.of());
}

public fetch(final Class<T> entityType, final FetchCategory fetchCategory) {
Expand All @@ -135,14 +158,6 @@ private void checkForExistence(final String propName) {
}
}

private static <T extends AbstractEntity<?>> fetch<T> copy(final fetch<T> fromFetch) {
final fetch<T> result = new fetch<>(fromFetch.entityType, fromFetch.fetchCategory, fromFetch.isInstrumented());
result.includedPropsWithModels.putAll(fromFetch.includedPropsWithModels);
result.includedProps.addAll(fromFetch.includedProps);
result.excludedProps.addAll(fromFetch.excludedProps);
return result;
}

/**
* Adds the property to this fetch model.
* </p>
Expand All @@ -160,9 +175,12 @@ private static <T extends AbstractEntity<?>> fetch<T> copy(final fetch<T> fromFe
*/
public fetch<T> with(final CharSequence propName) {
validate(propName.toString());
final fetch<T> result = copy(this);
result.includedProps.add(propName.toString());
return result;
return new fetch<>(entityType,
fetchCategory,
instrumented,
includedPropsWithModels,
setAppend(includedProps, propName.toString()),
excludedProps);
}

/**
Expand All @@ -176,12 +194,24 @@ public fetch<T> with(final CharSequence propName, final CharSequence... propName
for (final var name : propNames) {
validate(name.toString());
}
final fetch<T> result = copy(this);
result.includedProps.add(propName.toString());
for (final var name : propNames) {
result.includedProps.add(name.toString());

final Set<String> newIncludedProps;
{
final var builder = ImmutableSet.<String>builderWithExpectedSize(includedProps.size() + 1 + propNames.length)
.addAll(this.includedProps)
.add(propName.toString());
for (final var name : propNames) {
builder.add(name.toString());
}
newIncludedProps = builder.build();
}
return result;

return new fetch<>(entityType,
fetchCategory,
instrumented,
includedPropsWithModels,
newIncludedProps,
excludedProps);
}

/**
Expand All @@ -191,10 +221,18 @@ public fetch<T> with(final CharSequence propName, final CharSequence... propName
* @see #with(CharSequence)
*/
public fetch<T> with(final Iterable<? extends CharSequence> propNames) {
propNames.forEach(p -> validate(p.toString()));
final fetch<T> result = copy(this);
propNames.forEach(p -> result.includedProps.add(p.toString()));
return result;
if (Iterables.isEmpty(propNames)) {
return this;
}
else {
propNames.forEach(p -> validate(p.toString()));
return new fetch<>(entityType,
fetchCategory,
instrumented,
includedPropsWithModels,
concatSet(includedProps, Iterables.transform(propNames, CharSequence::toString)),
excludedProps);
}
}

/**
Expand All @@ -214,9 +252,12 @@ public fetch<T> with(final Iterable<? extends CharSequence> propNames) {
*/
public fetch<T> without(final CharSequence propName) {
validate(propName.toString());
final fetch<T> result = copy(this);
result.excludedProps.add(propName.toString());
return result;
return new fetch<>(entityType,
fetchCategory,
instrumented,
includedPropsWithModels,
includedProps,
setAppend(excludedProps, propName.toString()));
}

/**
Expand All @@ -230,12 +271,24 @@ public fetch<T> without(final CharSequence propName, final CharSequence... propN
for (final var name : propNames) {
validate(name.toString());
}
final fetch<T> result = copy(this);
result.excludedProps.add(propName.toString());
for (final var name : propNames) {
result.excludedProps.add(name.toString());

final Set<String> newExcludedProps;
{
final var builder = ImmutableSet.<String>builderWithExpectedSize(excludedProps.size() + 1 + propNames.length)
.addAll(this.excludedProps)
.add(propName.toString());
for (final var name : propNames) {
builder.add(name.toString());
}
newExcludedProps = builder.build();
}
return result;

return new fetch<>(entityType,
fetchCategory,
instrumented,
includedPropsWithModels,
includedProps,
newExcludedProps);
}

/**
Expand All @@ -245,10 +298,18 @@ public fetch<T> without(final CharSequence propName, final CharSequence... propN
* @see #without(CharSequence)
*/
public fetch<T> without(final Iterable<? extends CharSequence> propNames) {
propNames.forEach(p -> validate(p.toString()));
final fetch<T> result = copy(this);
propNames.forEach(p -> result.excludedProps.add(p.toString()));
return result;
if (Iterables.isEmpty(propNames)) {
return this;
}
else {
propNames.forEach(p -> validate(p.toString()));
return new fetch<>(entityType,
fetchCategory,
instrumented,
includedPropsWithModels,
includedProps,
concatSet(excludedProps, Iterables.transform(propNames, CharSequence::toString)));
}
}

/**
Expand All @@ -271,9 +332,12 @@ public fetch<T> with(final CharSequence propName, final fetch<? extends Abstract
}
}

final fetch<T> result = copy(this);
result.includedPropsWithModels.put(propName.toString(), fetchModel);
return result;
return new fetch<>(entityType,
fetchCategory,
instrumented,
ImmutableMapUtils.insert(includedPropsWithModels, propName.toString(), fetchModel),
includedProps,
excludedProps);
}

public Class<T> getEntityType() {
Expand All @@ -285,15 +349,15 @@ public boolean isInstrumented() {
}

public Map<String, fetch<? extends AbstractEntity<?>>> getIncludedPropsWithModels() {
return unmodifiableMap(includedPropsWithModels);
return includedPropsWithModels;
}

public Set<String> getIncludedProps() {
return unmodifiableSet(includedProps);
return includedProps;
}

public Set<String> getExcludedProps() {
return unmodifiableSet(excludedProps);
return excludedProps;
}

public FetchCategory getFetchCategory() {
Expand Down Expand Up @@ -373,22 +437,18 @@ private FetchCategory getMergedFetchCategory(final fetch<?> second) {
}

public fetch<?> unionWith(final fetch<?> second) {
if (second == null) {
if (second == null || second == this) {
return this;
}

final FetchCategory resultCategory = getMergedFetchCategory(second);
final fetch<T> result = new fetch<>(getEntityType(), resultCategory, (isInstrumented() || second.isInstrumented()));
result.includedProps.addAll(includedProps);
result.includedProps.addAll(second.includedProps);
result.excludedProps.addAll(excludedProps);
result.excludedProps.addAll(second.excludedProps);
includedPropsWithModels.forEach((prop, fetch) -> result.includedPropsWithModels.put(prop, fetch.unionWith(second.getIncludedPropsWithModels().get(prop))));

second.includedPropsWithModels.entrySet().stream()
.filter(entry -> !result.includedPropsWithModels.containsKey(entry.getKey()))
.forEach(entry -> result.includedPropsWithModels.put(entry.getKey(), entry.getValue().unionWith(getIncludedPropsWithModels().get(entry.getKey()))));

return result;
return new fetch<>(entityType,
getMergedFetchCategory(second),
(isInstrumented() || second.isInstrumented()),
ImmutableMapUtils.union((k, fetch1, fetch2) -> fetch1.unionWith(fetch2),
includedPropsWithModels,
second.includedPropsWithModels),
concatSet(includedProps, second.includedProps),
concatSet(excludedProps, second.excludedProps));
}

}

0 comments on commit a691ecd

Please sign in to comment.