return ps;
        }
        return new PrintStream(outputStream, true);
    }

    @Override
    public void log(Level level, String message, Throwable error) {
        requireNonNull(level, "level");
        requireNonNull(message, "message");
        if (level.ordinal() >= threshold.ordinal()) {
            out.println("[" + level.name() + "] " + message);
            if (error != null) {

  }

  @Override
  public C first() {
    // requireNonNull is safe because we checked the range is not empty in ContiguousSet.create.
    return requireNonNull(range.lowerBound.leastValueAbove(domain));
  }

  @Override
  public C last() {
    // requireNonNull is safe because we checked the range is not empty in ContiguousSet.create.
    return requireNonNull(range.upperBound.greatestValueBelow(domain));
  }

    return requireNonNull(outEdgeMap.get(edge));
  }

  @Override
  public N removeInEdge(E edge, boolean isSelfLoop) {
    if (isSelfLoop) {
      checkNonNegative(--selfLoopCount);
    }
    N previousNode = inEdgeMap.remove(edge);
    // We're relying on callers to call this method only with an edge that's in the graph.
    return requireNonNull(previousNode);
  }

  @Override

  @Override
  @SuppressWarnings("unchecked")
  public E get(int index) {
    checkElementIndex(index, size);
    // requireNonNull is safe because we guarantee that the first `size` elements are non-null.
    return (E) requireNonNull(array[index]);
  }

  // TODO(lowasser): benchmark optimizations for equals() and see if they're worthwhile

  // redeclare to help optimizers with b/310253115

          submittingTaskQueue.nextTask = task;
          // requireNonNull(delegate) is safe for reasons similar to requireNonNull(sequencer).
          submittingTaskQueue.nextExecutor = requireNonNull(delegate);
          delegate = null;
        } else {
          // requireNonNull(delegate) is safe for reasons similar to requireNonNull(sequencer).
          Executor localDelegate = requireNonNull(delegate);
          delegate = null;

### Best Practices

**Null Safety:**
```java
public Suggester(final Client client, final SuggestSettings settings) {
    this.client = Objects.requireNonNull(client, "client must not be null");
    this.settings = Objects.requireNonNull(settings, "settings must not be null");
}
```

**Logging with Context:**
```java
if (logger.isInfoEnabled()) {

import org.eclipse.aether.artifact.Artifact;
import org.eclipse.aether.repository.WorkspaceReader;
import org.eclipse.aether.repository.WorkspaceRepository;

import static java.util.Objects.requireNonNull;

/**
 * A maven workspace reader that delegates to a chain of other readers, effectively aggregating their contents.
 * <p>

    if (nodeU == null) {
      return false;
    }

    // requireNonNull is safe because of the edgeToReferenceNode check above.
    NetworkConnections<N, E> connectionsU = requireNonNull(nodeConnections.get(nodeU));
    N nodeV = connectionsU.adjacentNode(edge);
    NetworkConnections<N, E> connectionsV = requireNonNull(nodeConnections.get(nodeV));
    connectionsU.removeOutEdge(edge);

    // requireNonNull is safe because we use indexes that were populated by the constructor.
    V value = requireNonNull(values[rowIndex][columnIndex]);
    return cellOf(rowKey, columnKey, value);
  }

  @Override
  V getValue(int index) {
    // requireNonNull is safe because we use indexes that were populated by the constructor.

import java.io.Serializable;

import static java.util.Objects.requireNonNull;

public abstract class BaseObject implements Serializable, Cloneable {
    protected transient ChildrenTracking childrenTracking;

    protected Object delegate;

    public BaseObject() {}

    public BaseObject(Object delegate, BaseObject parent) {
        this.delegate = requireNonNull(delegate, "delegate cannot be null");