build.gradle

        // un7z
        compile 'org.apache.commons:commons-compress:1.15'
        compile 'org.tukaani:xz:1.8'

package com.jdsoft.util;

import org.apache.commons.compress.archivers.sevenz.SevenZArchiveEntry;
import org.apache.commons.compress.archivers.sevenz.SevenZFile;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

public class Un7zipUtils {

    /**
     * 解压 7z 格式的压缩文件 (apache的common-compress)
     * @param orgPath 源压缩文件地址
     * @param tarPath 解压后存放的目录地址
     */
    public static void apacheUn7Z(String orgPath, String tarPath) {
        try {
            SevenZFile sevenZFile = new SevenZFile(new File(orgPath));
            SevenZArchiveEntry entry = sevenZFile.getNextEntry();
            while (entry != null) {
                if (entry.isDirectory()) {
                    new File(tarPath + File.separator + entry.getName()).mkdirs();
                    entry = sevenZFile.getNextEntry();
                    continue;
                }
                FileOutputStream out = new FileOutputStream(tarPath
                        + File.separator + entry.getName());
                byte[] content = new byte[(int) entry.getSize()];
                sevenZFile.read(content, 0, content.length);
                out.write(content);
                out.close();
                entry = sevenZFile.getNextEntry();
            }
            sevenZFile.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}