PrintWriter writer = new PrintWriter(buffer);

        writer.print(problems.size());
        writer.print((problems.size() == 1) ? " problem was " : " problems were ");
        writer.print("encountered while building the effective settings");
        writer.println();

        for (SettingsProblem problem : problems) {
            writer.print("[");
            writer.print(problem.getSeverity());

 */
package org.codelibs.fess.exception;

/**
 * Exception thrown when command execution fails.
 * This exception indicates that an external command or process execution encountered an error.
 */
public class CommandExecutionException extends FessSystemException {

    private static final long serialVersionUID = 1L;

    /**
     * Constructor with error message.

        StringBuilder buffer = new StringBuilder(256);

        buffer.append("Missing:").append(LS);
        buffer.append("----------").append(LS);

        int counter = 0;

        for (Artifact artifact : artifacts) {
            String message = (++counter) + ") " + artifact.getId();

            buffer.append(constructMissingArtifactMessage(
                    message,
                    "  ",

        try {
            toolchainBuilder.build(request);
        } catch (ToolchainsBuildingException e) {
            assertEquals(
                    "1 problem was encountered while building the effective toolchains" + LS
                            + "[FATAL] Non-parseable toolchains (memory): MESSAGE @ line 4, column 2" + LS,
                    e.getMessage());
        }
    }

    /** Current page number. */
    private int currentPageNumber;

    /** ID of the failure URL record. */
    public String id;

    /** Name of the thread that encountered the failure. */
    public String threadName;

    /** Number of errors encountered for this URL. */
    public String errorCount;

    /** Last time this URL was accessed. */
    public String lastAccessTime;

    /**

    }

    /**
     * Increment requests sent counter
     */
    public void incrementRequestsSent() {
        requestsSent.incrementAndGet();
    }

    /**
     * Increment requests received counter
     */
    public void incrementRequestsReceived() {
        requestsReceived.incrementAndGet();
    }

    /**
     * Increment error counter
     */
    public void incrementErrors() {

 */
@Deprecated(since = "4.0.0")
public interface ModelProblemCollectorExt extends ModelProblemCollector {

    /**
     * The collected problems.
     * @return a list of model problems encountered, never {@code null}
     */
    List<ModelProblem> getProblems();

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.exception;

/**
 * Exception thrown when an invalid access token is encountered.
 * This exception is typically used in authentication and authorization contexts
 * where a provided access token is invalid, expired, or malformed.
 */
public class InvalidAccessTokenException extends FessSystemException {

@Experimental
public interface ModelTransformer {

    /**
     * Apply a transformation on the file model.
     *
     * @param model the input model
     * @param problems the problem collector to report any issues encountered during transformation
     * @return the transformed model, or the input model if no transformation is needed
     */
    @Nonnull
    Model transform(

While waiting and talking to your crush, from time to time, you check the number displayed on the counter to see if it's your turn already.

Then at some point, it finally is your turn. You go to the counter, get your burgers and come back to the table.

<img src="/img/async/concurrent-burgers/concurrent-burgers-06.png" class="illustration">