## Project Overview

curl4j is a simple cURL-like Java HTTP client library providing a fluent API for building HTTP requests. It's designed to be minimal with only Apache Commons IO as a dependency.

## Directory Structure

```
curl4j/
├── src/
│   ├── main/java/org/codelibs/curl/
│   │   ├── Curl.java              # Static entry point with factory methods

import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.common.testing.NullPointerTester;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.ArrayList;
import java.util.List;
import junit.framework.TestSuite;

import static org.junit.Assert.assertThrows;

import com.google.common.collect.ImmutableList;
import com.google.common.testing.NullPointerTester;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.ArrayList;
import java.util.List;
import junit.framework.TestSuite;

}

public final class okhttp3/Cache : java/io/Closeable, java/io/Flushable {
	public static final field Companion Lokhttp3/Cache$Companion;
	public final fun -deprecated_directory ()Ljava/io/File;
	public fun <init> (Ljava/io/File;J)V
	public fun <init> (Lokio/FileSystem;Lokio/Path;J)V
	public fun close ()V
	public final fun delete ()V
	public final fun directory ()Ljava/io/File;
	public final fun directoryPath ()Lokio/Path;

}

public final class okhttp3/Cache : java/io/Closeable, java/io/Flushable {
	public static final field Companion Lokhttp3/Cache$Companion;
	public final fun -deprecated_directory ()Ljava/io/File;
	public fun <init> (Ljava/io/File;J)V
	public fun <init> (Lokio/FileSystem;Lokio/Path;J)V
	public fun close ()V
	public final fun delete ()V
	public final fun directory ()Ljava/io/File;
	public final fun directoryPath ()Lokio/Path;

        DataStoreException withNPE = new DataStoreException("NPE Error", new NullPointerException("Null value"));
        DataStoreException withCustom = new DataStoreException("Custom Error", new FessSystemException("System error"));

        assertTrue(withIOException.getCause() instanceof java.io.IOException);

        // Test with IOException
        Throwable ioCause = new java.io.IOException("IO error");
        GsaConfigException ioException = new GsaConfigException("GSA IO error", ioCause);
        assertNotNull(ioException);
        assertTrue(ioException.getCause() instanceof java.io.IOException);

        // Test with custom exception

        String message = "IO error during thumbnail generation";
        Exception checkedException = new java.io.IOException("File not found");
        ThumbnailGenerationException exception = new ThumbnailGenerationException(message, checkedException);

        assertEquals(message, exception.getMessage());
        assertTrue(exception.getCause() instanceof java.io.IOException);

    <maven-toolchains-plugin.version>3.2.0</maven-toolchains-plugin.version>
    <mockito.version>4.11.0</mockito.version>
    <plexus-io.version>3.6.0</plexus-io.version> <!-- We need at least 3.5.1 to avoid https://github.com/codehaus-plexus/plexus-io/issues/109. Once we upgrade maven-jar-plugin itself to a version new enough to depend on 3.5.1 or higher, we can remove this override. -->

├── concurrent/  # Concurrency utilities
├── convert/     # Type conversion (*ConversionUtil)
├── crypto/      # Cipher & encryption (CachedCipher)
├── exception/   # Runtime exception wrappers
├── io/          # I/O & resource utilities
├── jar/         # JAR file utilities
├── lang/        # Reflection & language utilities
├── log/         # Logging utilities
├── message/     # Message resource handling