*   <li>{@link #JAVA_COMPILER}, while still listed as required as of Java 15, is typically not
   *       available even under older version.
   *   <li>Any property may be cleared through APIs like {@link System#clearProperty}.
   *   <li>Unusual environments like GWT may have their own special handling of system properties.
   * </ul>
   *
   * <p>Note that {@code StandardSystemProperty} does not provide constants for more recently added

   *   <li>{@link #JAVA_COMPILER}, while still listed as required as of Java 15, is typically not
   *       available even under older version.
   *   <li>Any property may be cleared through APIs like {@link System#clearProperty}.
   *   <li>Unusual environments like GWT may have their own special handling of system properties.
   * </ul>
   *
   * <p>Note that {@code StandardSystemProperty} does not provide constants for more recently added

        assertEquals("underscore", ResourceUtil.resolve(value));

        // Clean up test properties
        System.clearProperty("var1");
        System.clearProperty("var2");
        System.clearProperty("special");
        System.clearProperty("123");
        System.clearProperty("test_var");
    }

    @Test
    public void test_resolve_edgeCases() {
        // Test empty property replacement

            String floatValue = fessConfig.get(floatKey);
            assertEquals("45.67", floatValue);
        } finally {
            System.clearProperty(Constants.FESS_CONFIG_PREFIX + intKey);
            System.clearProperty(Constants.FESS_CONFIG_PREFIX + floatKey);
        }
    }

    // Test getting boolean configuration values
    @Test
    public void test_get_booleanValues() {

    public void test_getSearchEngineHttpAddress_null() {
        // Clear the system property to test null case
        String originalValue = System.getProperty(Constants.FESS_SEARCH_ENGINE_HTTP_ADDRESS);
        System.clearProperty(Constants.FESS_SEARCH_ENGINE_HTTP_ADDRESS);

        try {
            String result = SystemUtil.getSearchEngineHttpAddress();
            assertNull(result);
        } finally {

        assertTrue(cmdList.contains("-Dapp.module.feature2=disabled"));

        // Clean up
        System.clearProperty("app.module.feature1");
        System.clearProperty("app.module.feature2");
        System.clearProperty("app.service.api");
        System.clearProperty("config.app.module");
    }

    // Test invalid regex in custom properties
    @Test

        }
        // Clear system properties that might affect the test
        System.clearProperty("jcifs.properties");
        System.clearProperty("java.protocol.handler.pkgs");
        // Clear jcifs-specific properties to prevent test interference
        System.clearProperty("jcifs.smb.client.nativeOs");
        System.clearProperty("jcifs.smb.client.nativeLanMan");
    }

    @Test

            assertFalse(content.contains("${fess.dictionary.path}"));
        } finally {
            // Restore original property
            if (originalPath.isEmpty()) {
                System.clearProperty("fess.dictionary.path");
            } else {
                System.setProperty("fess.dictionary.path", originalPath);
            }
        }
    }

    @Test

        System.clearProperty(Constants.MAVEN_LOGGER_DEFAULT_LOG_LEVEL);
    }

    @AfterEach
    void tearDown() {
        // Restore original system property
        if (originalSystemProperty != null) {
            System.setProperty(Constants.MAVEN_LOGGER_DEFAULT_LOG_LEVEL, originalSystemProperty);
        } else {
            System.clearProperty(Constants.MAVEN_LOGGER_DEFAULT_LOG_LEVEL);
        }

            assertEquals(Constants.PROCESS_TYPE_REPLACE, ptList.get(0));
        } finally {
            System.clearProperty("lasta.env");
        }
    }

    @Test
    public void test_getProcessTypeList_defaultMode() {
        System.clearProperty("lasta.env");
        final List<String> ptList = pathMappingHelper.getProcessTypeList();
        assertEquals(2, ptList.size());