Thread thread2 = new Thread(() -> {
            for (int i = 0; i < 100; i++) {
                urlFilter.addExclude(".*\\.type" + i + "$");
            }
        });

        thread1.start();
        thread2.start();

        thread1.join();
        thread2.join();

        // Should complete without errors
        assertNotNull(urlFilter);
    }

    /**
     * Test boundary conditions

                    valueSet.add(source.get("field1").toString());
                    count.getAndIncrement();
                }
            });
        }

        for (Thread th : threads) {
            th.start();
        }
        for (Thread th : threads) {
            th.join();
        }
        assertEquals(num, count.get());
        assertEquals(num, valueSet.size());

                            exceptions.add(e);
                        }
                    }
                }
            });
        }

        // Start all threads
        for (Thread thread : threads) {
            thread.start();
        }

        // Wait for all threads to complete
        for (Thread thread : threads) {
            thread.join();
        }

    }

    /**
     * Reads up to len bytes of data from the input stream into an array of bytes.
     *
     * @param b the buffer into which the data is read
     * @param off the start offset in array b at which the data is written
     * @param len the maximum number of bytes to read
     * @return the total number of bytes read into the buffer, or -1 if there is no more data

this.prop=c,this.easing=e||"swing",this.options=b,this.start=this.now=this.cur(),this.end=d,this.unit=f||(n.cssNumber[c]?"":"px")},cur:function(){var a=Kb.propHooks[this.prop];return a&&a.get?a.get(this):Kb.propHooks._default.get(this)},run:function(a){var b,c=Kb.propHooks[this.prop];return this.pos=b=this.options.duration?n.easing[this.easing](a,this.options.duration*a,0,1,this.options.duration):a,this.now=(this.end-this.start)*b+this.start,this.options.step&&this.options.step.call(this.elem,th...

                            exceptions.add(e);
                        }
                    }
                }
            });
        }

        // Start all threads
        for (Thread thread : threads) {
            thread.start();
        }

        // Wait for all threads
        for (Thread thread : threads) {
            thread.join();
        }

        // Verify results

     */
    public String execute() {
        parentThread = new Thread(this, "Crawler-" + crawlerContext.sessionId);
        parentThread.setDaemon(daemon);
        parentThread.start();
        if (!background) {
            awaitTermination();
        }
        return crawlerContext.sessionId;
    }

    /**
     * Waits for the crawling process to terminate indefinitely.
     */

- **HTTP Client**: Apache HttpComponents
- **Content Extraction**: Apache Tika, Apache POI, PDFBox
- **Testing**: JUnit 4, UTFlute, Testcontainers
- **Storage Backends**: OpenSearch, Memory-based

## Quick Start

### Prerequisites

- Java 21 or higher
- Maven 3.6 or higher

### Installation

Add the following dependency to your `pom.xml`:

```xml
<dependency>
    <groupId>org.codelibs.fess</groupId>

            try {
                insert(urlQueue);
            } catch (final Exception e) {
                logger.warn("Failed to restore " + urlQueue, e);
            }
        }));
    }

    /**
     * Clears the cache.
     */
    public void clearCache() {
        sessionCache.clear();
    }

    /**

- **Apache Lucene**: Query parsing and text analysis
- **ICU4J**: Unicode text processing and normalization
- **JUnit 4**: Testing framework
- **Maven**: Build and dependency management

## Quick Start

### Prerequisites

- Java 21 or higher
- OpenSearch/Elasticsearch cluster (2.x+ recommended)
- Maven 3.8+ for building from source

### Installation

Add the dependency to your `pom.xml`:

```xml