49 lines
946 B
Java
49 lines
946 B
Java
package eu.dnetlib.miscutils.collections;
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import java.util.List;
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import com.google.common.collect.Lists;
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/**
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* Utility class which checks ensures that a given collection is not null.
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*
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* <p>
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* CXF for example cannot distinguish from nulls. This helper allows you write:
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* </p>
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*
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* <pre>
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* for(String bla : EnsureCollection.list(somecode())) {....}
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* </pre>
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*
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* @author marko
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*
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*/
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public class EnsureCollection {
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/**
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* returns the argument or a new list if the argument is null.
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*
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* @param <T> a type
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* @param aList a list
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* @return passthrough or empty list
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*/
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public static <T> List<T> list(final List<T> aList) {
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if (aList == null)
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return Lists.newArrayList();
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return aList;
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}
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/**
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* Alias for static imports.
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*
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* @param <T> a type
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* @param aList a list
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* @return passthrough or empty list
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*/
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public static <T> List<T> notNullList(final List<T> aList) {
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return list(aList);
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}
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}
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