CachingAppender.java

package jetbrains.mps.testbench.util;

/*Generated by MPS */

import org.apache.log4j.AppenderSkeleton;
import java.util.List;
import java.util.ArrayList;
import com.intellij.openapi.util.Pair;
import org.apache.log4j.Level;
import org.apache.log4j.varia.LevelRangeFilter;
import org.apache.log4j.spi.LoggingEvent;
import java.util.Arrays;

/**
 * fyodor, Aug 18, 2010
 */
public class CachingAppender extends AppenderSkeleton implements Output {
  private int myEvents;
  private List<String> myMessages = new ArrayList<String>();
  private List<Pair<Integer, String>> myExpectedEvents = new ArrayList<Pair<Integer, String>>();
  private List<Pair<Integer, String>> myReceivedExpectedEvents = new ArrayList<Pair<Integer, String>>();

  public CachingAppender(Level watchLevel) {
    final LevelRangeFilter newFilter = new LevelRangeFilter();
    newFilter.setLevelMin(watchLevel);
    this.addFilter(newFilter);
  }

  @Override
  protected void append(LoggingEvent loggingEvent) {
    if (!(isExpected(loggingEvent))) {
      myEvents++;
      myMessages.add(loggingEvent.getRenderedMessage());
      String[] stackTrace = loggingEvent.getThrowableStrRep();
      if (stackTrace != null) {
        myMessages.add("++ =============StackTrace================");
        myMessages.addAll(Arrays.asList(stackTrace));
        myMessages.add("-- =============StackTrace================");
      }
    }
  }

  private boolean isExpected(LoggingEvent event) {
    for (Pair<Integer, String> pr : myExpectedEvents) {
      if (event.getLevel().isGreaterOrEqual(Level.toLevel(pr.first))) {
        if (pr.second == null || pr.second.equals(event.getRenderedMessage())) {
          myReceivedExpectedEvents.add(pr);
          return true;
        }
      }
    }
    return false;
  }

  @Override
  public boolean isNotEmpty() {
    return myEvents > 0;
  }

  @Override
  public String getDescription() {
    return myEvents + " events";
  }

  @Override
  public String getText() {
    StringBuilder sb = new StringBuilder();
    String sep = "";
    for (String s : myMessages) {
      sb.append(sep);
      sep = "\n";
      sb.append(s);
    }
    sb.append("\n");
    return sb.toString();
  }

  @Override
  public void close() {
  }

  @Override
  public boolean requiresLayout() {
    return false;
  }

  public void sealEvents() {
    List<Pair<Integer, String>> list = new ArrayList<Pair<Integer, String>>(myExpectedEvents);
    list.removeAll(myReceivedExpectedEvents);
    for (Pair<Integer, String> pr : list) {
      myEvents++;
      myMessages.add("MISSING: " + pr.second);
    }
  }

  public void expectEvent(int level, String text) {
    myExpectedEvents.add(new Pair<Integer, String>(level, text));
  }
}