org.apache.juneau.internal.SetBuilder Maven / Gradle / Ivy
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// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance *
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// * *
// * http://www.apache.org/licenses/LICENSE-2.0 *
// * *
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// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the *
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package org.apache.juneau.internal;
import static org.apache.juneau.common.internal.StringUtils.*;
import static org.apache.juneau.common.internal.ThrowableUtils.*;
import static org.apache.juneau.internal.ConverterUtils.*;
import static java.util.Collections.*;
import java.lang.reflect.*;
import java.util.*;
import org.apache.juneau.collections.*;
import org.apache.juneau.parser.*;
/**
* Builder for sets.
*
* See Also:
*
*
* @param Element type.
*/
public final class SetBuilder {
private Set set;
private boolean unmodifiable, sparse;
private Comparator comparator;
private Class elementType;
private Type[] elementTypeArgs;
/**
* Constructor.
*
* @param elementType The element type.
* @param elementTypeArgs The element type generic arguments if there are any.
*/
public SetBuilder(Class elementType, Type...elementTypeArgs) {
this.elementType = elementType;
this.elementTypeArgs = elementTypeArgs;
}
/**
* Constructor.
*
* @param addTo The set to add to.
*/
public SetBuilder(Set addTo) {
this.set = addTo;
}
/**
* Builds the set.
*
* @return A set conforming to the settings on this builder.
*/
public Set build() {
if (sparse) {
if (set != null && set.isEmpty())
set = null;
} else {
if (set == null)
set = new LinkedHashSet<>(0);
}
if (set != null) {
if (comparator != null) {
Set s = new TreeSet<>(comparator);
s.addAll(set);
set = s;
}
if (unmodifiable)
set = unmodifiableSet(set);
}
return set;
}
/**
* When specified, the {@link #build()} method will return null if the set is empty.
*
*
* Otherwise {@link #build()} will never return null .
*
* @return This object.
*/
public SetBuilder sparse() {
this.sparse = true;
return this;
}
/**
* When specified, {@link #build()} will return an unmodifiable set.
*
* @return This object.
*/
public SetBuilder unmodifiable() {
this.unmodifiable = true;
return this;
}
/**
* Forces the existing set to be copied instead of appended to.
*
* @return This object.
*/
public SetBuilder copy() {
if (set != null)
set = new LinkedHashSet<>(set);
return this;
}
/**
* Converts the set into a {@link SortedSet}.
*
* @return This object.
*/
@SuppressWarnings("unchecked")
public SetBuilder sorted() {
return sorted((Comparator)Comparator.naturalOrder());
}
/**
* Converts the set into a {@link SortedSet} using the specified comparator.
*
* @param comparator The comparator to use for sorting.
* @return This object.
*/
public SetBuilder sorted(Comparator comparator) {
this.comparator = comparator;
return this;
}
/**
* Appends the contents of the specified collection into this set.
*
*
* This is a no-op if the value is null .
*
* @param value The collection to add to this set.
* @return This object.
*/
public SetBuilder addAll(Collection value) {
if (value != null) {
if (set == null)
set = new LinkedHashSet<>(value);
else
set.addAll(value);
}
return this;
}
/**
* Adds a single value to this set.
*
* @param value The value to add to this set.
* @return This object.
*/
public SetBuilder add(E value) {
if (set == null)
set = new LinkedHashSet<>();
set.add(value);
return this;
}
/**
* Adds multiple values to this set.
*
* @param values The values to add to this set.
* @return This object.
*/
@SuppressWarnings("unchecked")
public SetBuilder add(E...values) {
for (E v : values)
add(v);
return this;
}
/**
* Adds entries to this set via JSON array strings.
*
* @param values The JSON array strings to parse and add to this set.
* @return This object.
*/
public SetBuilder addJson(String...values) {
return addAny((Object[])values);
}
/**
* Adds arbitrary values to this set.
*
*
* Objects can be any of the following:
*
* - The same type or convertible to the element type of this set.
*
- Collections or arrays of anything on this set.
*
- JSON array strings parsed and convertible to the element type of this set.
*
*
* @param values The values to add.
* @return This object.
*/
public SetBuilder addAny(Object...values) {
if (elementType == null)
throw new IllegalStateException("Unknown element type. Cannot use this method.");
try {
if (values != null) {
for (Object o : values) {
if (o != null) {
if (o instanceof Collection) {
((Collection)o).forEach(x -> addAny(x));
} else if (o.getClass().isArray()) {
for (int i = 0; i < Array.getLength(o); i++)
addAny(Array.get(o, i));
} else if (isJsonArray(o, false)) {
new JsonList(o.toString()).forEach(x -> addAny(x));
} else if (elementType.isInstance(o)) {
add(elementType.cast(o));
} else {
add(toType(o, elementType, elementTypeArgs));
}
}
}
}
} catch (ParseException e) {
throw asRuntimeException(e);
}
return this;
}
/**
* Adds a value to this set if the specified flag is true.
*
* @param flag The flag.
* @param value The value.
* @return This object.
*/
public SetBuilder addIf(boolean flag, E value) {
if (flag)
add(value);
return this;
}
}