本文整理了Java中java.util.Hashtable.putIfAbsent()方法的一些代码示例，展示了Hashtable.putIfAbsent()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。Hashtable.putIfAbsent()方法的具体详情如下：
包路径：java.util.Hashtable
类名称：Hashtable
方法名：putIfAbsent

Hashtable.putIfAbsent介绍

暂无

代码示例

代码示例来源：origin: dCache/dcache

private void merge( String user , Boolean access ){
  _users.putIfAbsent(user, access);
}
//

代码示例来源：origin: sboesebeck/morphium

public void addSyncListener(Class type, T cl) {
  listenerForType.putIfAbsent(type, new Vector<>());
  listenerForType.get(type).add(cl);
}

代码示例来源：origin: org.eclipse.persistence/org.eclipse.persistence.core

@Override
public synchronized V putIfAbsent(K key, V value) {
  // Must trigger add events if tracked or uow.
  if (hasTrackedPropertyChangeListener()) {
    V current = getDelegate().get(key);
    if (current == null) {
      V v = getDelegate().put(key, value);
      raiseAddChangeEvent(key, value);
      return v;
    }
    return current;
  }
  return getDelegate().putIfAbsent(key, value);
}

代码示例来源：origin: com.haulmont.thirdparty/eclipselink

@Override
public synchronized V putIfAbsent(K key, V value) {
  // Must trigger add events if tracked or uow.
  if (hasTrackedPropertyChangeListener()) {
    V current = getDelegate().get(key);
    if (current == null) {
      V v = getDelegate().put(key, value);
      raiseAddChangeEvent(key, value);
      return v;
    }
    return current;
  }
  return getDelegate().putIfAbsent(key, value);
}

代码示例来源：origin: octo-online/reactive-audit

@Test(expected = ReactiveAuditException.class)
public void putIfAbsent()
{
  ReactiveAudit.off.commit();
  Hashtable hash=new Hashtable();
  TestTools.strict.commit();
  hash.putIfAbsent(null,null);
}
@Test(expected = ReactiveAuditException.class)