### I/O Layer

- **`ContentCache`**: In-memory or file-based caching. Implements `Closeable` and auto-deletes file cache on close.

- **`ContentOutputStream`**: Extends `DeferredFileOutputStream`. Writes to memory until threshold (default 1MB) exceeded, then spills to temp file.

## Technical Details

- **Java Version**: 17+
- **Dependencies**: Apache Commons IO (runtime), JUnit 4 (test)

import static org.junit.jupiter.api.Assertions.assertNotSame;

import org.codelibs.fess.unit.UnitFessTestCase;
import org.junit.jupiter.api.Test;

public class FessUserNotFoundExceptionTest extends UnitFessTestCase {

    @Test
    public void test_constructor_withValidUsername() {
        // Test with a normal username
        String username = "testuser";

 */
package org.codelibs.fess.chat;

import java.util.ArrayList;
import java.util.List;

import org.codelibs.fess.unit.UnitFessTestCase;
import org.junit.jupiter.api.Test;

public class ChatPhaseCallbackTest extends UnitFessTestCase {

    @Test
    public void test_phaseConstants() {
        assertEquals("intent", ChatPhaseCallback.PHASE_INTENT);
        assertEquals("search", ChatPhaseCallback.PHASE_SEARCH);

import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

import org.codelibs.fess.unit.UnitFessTestCase;
import org.junit.jupiter.api.Test;

public class DictionaryExpiredExceptionTest extends UnitFessTestCase {

    @Test
    public void test_constructor() {
        // Test default constructor
        DictionaryExpiredException exception = new DictionaryExpiredException();
        assertNotNull(exception);

import org.codelibs.fess.unit.UnitFessTestCase;
import org.codelibs.fess.util.ComponentUtil;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.TestInfo;

public class FessApiFailureHookTest extends UnitFessTestCase {

    private FessApiFailureHook apiFailureHook;
    private FessConfig originalFessConfig;

    @Override
    protected void setUp(TestInfo testInfo) throws Exception {

import org.lastaflute.web.ruts.process.ActionRuntime;
import org.lastaflute.web.servlet.request.RequestManager;
import org.lastaflute.web.servlet.request.SimpleRequestManager;

public class FessUserTimeZoneProcessProviderTest extends UnitFessTestCase {

    private FessUserTimeZoneProcessProvider provider;
    private RequestManager requestManager;

    @Override
    protected void setUp(TestInfo testInfo) throws Exception {

import java.util.Arrays;
import java.util.Collections;
import java.util.List;

import org.codelibs.fess.unit.UnitFessTestCase;
import org.junit.jupiter.api.Test;

public class RelevanceEvaluationResultTest extends UnitFessTestCase {

    @Test
    public void test_withRelevantDocs() {
        List<String> docIds = Arrays.asList("doc1", "doc2", "doc3");
        List<Integer> indexes = Arrays.asList(1, 2, 3);

 */
package org.codelibs.fess.taglib;

import java.util.Date;

import org.codelibs.fess.unit.UnitFessTestCase;
import org.junit.jupiter.api.Test;

public class FessFunctionsTest extends UnitFessTestCase {
    @Test
    public void test_formatNumber() {
        assertEquals("0", FessFunctions.formatNumber(0, "###,###"));
        assertEquals("1,000", FessFunctions.formatNumber(1000, "###,###"));

f.asyncValidators||(f.asyncValidators={}),f.asyncValidators[a]?e=f.asyncValidators[a]:(e=new d(c,b),f.asyncValidators[a]=e),e},a.formUtils=a.extend(a.formUtils||{},{asyncValidation:function(a,b,c){return this.warn("Use of deprecated function $.formUtils.asyncValidation, use $.formUtils.addAsyncValidator() instead"),d.loadInstance(a,b,c)},addAsyncValidator:function(b){var c=a.extend({},b),e=c.validatorFunction;c.async=!0,c.validatorFunction=function(a,b,f,g,h,i){var j=d.loadInstance(this.name,b,h);return j.ru...

import org.lastaflute.web.response.HtmlResponse;
import org.lastaflute.web.validation.VaErrorHook;

import jakarta.annotation.Resource;

/**
 * Action for user profile operations.
 */
public class ProfileAction extends FessSearchAction {

    /**
     * Default constructor.
     */
    public ProfileAction() {
        super();
    }

    private static final Logger logger = LogManager.getLogger(ProfileAction.class);