com.whaleal.icefrog.extra.compress.extractor.StreamExtractor Maven / Gradle / Ivy

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package com.whaleal.icefrog.extra.compress.extractor;

import com.whaleal.icefrog.core.io.FileUtil;
import com.whaleal.icefrog.core.io.IORuntimeException;
import com.whaleal.icefrog.core.io.IoUtil;
import com.whaleal.icefrog.core.lang.Preconditions;
import com.whaleal.icefrog.core.lang.Filter;
import com.whaleal.icefrog.core.util.StrUtil;
import com.whaleal.icefrog.extra.compress.CompressException;
import org.apache.commons.compress.archivers.ArchiveInputStream;
import org.apache.commons.compress.archivers.ArchiveEntry;
import org.apache.commons.compress.archivers.ArchiveException;
import org.apache.commons.compress.archivers.ArchiveStreamFactory;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;

/**
 * 数据解压器，即将归档打包的数据释放
 *
 * @author Looly
 * @author wh
 * @since 1.0.0
 */
public class StreamExtractor implements Extractor{

	private final ArchiveInputStream in;

	/**
	 * 构造
	 *
	 * @param charset      编码
	 * @param file         包文件
	 */
	public StreamExtractor(Charset charset, File file) {
		this(charset, null, file);
	}

	/**
	 * 构造
	 *
	 * @param charset      编码
	 * @param archiverName 归档包格式，null表示自动检测
	 * @param file         包文件
	 */
	public StreamExtractor(Charset charset, String archiverName, File file) {
		this(charset, archiverName, FileUtil.getInputStream(file));
	}

	/**
	 * 构造
	 *
	 * @param charset 编码
	 * @param in      包流
	 */
	public StreamExtractor(Charset charset, InputStream in) {
		this(charset, null, in);
	}

	/**
	 * 构造
	 *
	 * @param charset      编码
	 * @param archiverName 归档包格式，null表示自动检测
	 * @param in           包流
	 */
	public StreamExtractor(Charset charset, String archiverName, InputStream in) {
		final ArchiveStreamFactory factory = new ArchiveStreamFactory(charset.name());
		try {
			in = IoUtil.toBuffered(in);
			if (StrUtil.isBlank(archiverName)) {
				this.in = factory.createArchiveInputStream(in);
			} else {
				this.in = factory.createArchiveInputStream(archiverName, in);
			}
		} catch (ArchiveException e) {
			throw new CompressException(e);
		}
	}

	/**
	 * 释放（解压）到指定目录，结束后自动关闭流，此方法只能调用一次
	 *
	 * @param targetDir 目标目录
	 * @param filter    解压文件过滤器，用于指定需要释放的文件，null表示不过滤。当{@link Filter#accept(Object)}为true时释放。
	 */
	@Override
	public void extract(File targetDir, Filter filter) {
		try {
			extractInternal(targetDir, filter);
		} catch (IOException e) {
			throw new IORuntimeException(e);
		} finally {
			close();
		}
	}

	/**
	 * 释放（解压）到指定目录
	 *
	 * @param targetDir 目标目录
	 * @param filter    解压文件过滤器，用于指定需要释放的文件，null表示不过滤。当{@link Filter#accept(Object)}为true时释放。
	 * @throws IOException IO异常
	 */
	private void extractInternal(File targetDir, Filter filter) throws IOException {
		Preconditions.isTrue(null != targetDir && ((false == targetDir.exists()) || targetDir.isDirectory()), "target must be dir.");
		final ArchiveInputStream in = this.in;
		ArchiveEntry entry;
		File outItemFile;
		while (null != (entry = in.getNextEntry())) {
			if (false == in.canReadEntryData(entry)) {
				// 无法读取的文件直接跳过
				continue;
			}
			outItemFile = FileUtil.file(targetDir, entry.getName());
			if (entry.isDirectory()) {
				// 创建对应目录
				//noinspection ResultOfMethodCallIgnored
				outItemFile.mkdirs();
			} else {
				FileUtil.writeFromStream(in, outItemFile, false);
			}
		}
	}

	@Override
	public void close() {
		IoUtil.close(this.in);
	}
}