Example usage for java.util.concurrent ConcurrentSkipListMap putIfAbsent

Introduction

In this page you can find the example usage for java.util.concurrent ConcurrentSkipListMap putIfAbsent.

Prototype

public V putIfAbsent(K key, V value) 

Source Link

Usage

From source file:com.doctor.other.concurrent_hash_map_based_table.ConcurrentHashMapBasedTable.java

/**
 * /*from   w ww .  j a  v a2s.  c  o m*/
 * @param rowKey
 * @param columnKey
 * @param timesplice
 *            ?:201572701
 * @param value
 * @return
 */
public boolean put(final String rowKey, final String columnKey, final String timesplice, final T value) {
    Preconditions.checkState(StringUtils.isNotBlank(rowKey), "rowKey is blank");
    Preconditions.checkState(StringUtils.isNotBlank(columnKey), "columnKey is blank");
    Preconditions.checkState(StringUtils.isNotBlank(timesplice), "timesplice is blank");
    Preconditions.checkNotNull(value, "value is null");

    ConcurrentHashMap<String, ConcurrentSkipListMap<String, ConcurrentSet<T>>> row = table.get(rowKey);
    if (row == null) {
        table.putIfAbsent(rowKey,
                new ConcurrentHashMap<String, ConcurrentSkipListMap<String, ConcurrentSet<T>>>());
    }

    row = table.get(rowKey);

    ConcurrentSkipListMap<String, ConcurrentSet<T>> column = row.get(columnKey);
    if (column == null) {
        row.putIfAbsent(columnKey, new ConcurrentSkipListMap<String, ConcurrentSet<T>>());
    }

    column = row.get(columnKey);

    ConcurrentSet<T> values = column.get(timesplice);
    if (values == null) {
        column.putIfAbsent(timesplice, new ConcurrentSet<>());
    }

    values = column.get(timesplice);
    return values.add(value);
}

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