34 lines
693 B
Java
34 lines
693 B
Java
package org.thoughtcrime.securesms.util;
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import androidx.annotation.MainThread;
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import androidx.annotation.NonNull;
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import androidx.recyclerview.widget.RecyclerView;
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import java.util.HashMap;
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import java.util.Map;
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/**
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* Useful for generate ID's to be used with
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* {@link RecyclerView.Adapter#getItemId(int)} when you otherwise don't
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* have a good way to generate an ID.
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*/
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public class StableIdGenerator<E> {
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private final Map<E, Long> keys = new HashMap<>();
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private long index = 1;
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@MainThread
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public long getId(@NonNull E item) {
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if (keys.containsKey(item)) {
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return keys.get(item);
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}
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long key = index++;
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keys.put(item, key);
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return key;
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}
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}
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