结论:
1.在jar包代码中要使用绝对路径,路径以 / 开始。
2.在jar包代码中使用相对路径的起点是和jar所在目录。比如说test.jar所处位置为/opt/test/test.jar,那么你在代码中写相对路径:“pathTest/haha.txt”,那么实际指向的位置为/opt/test/pathTest/haha.txt
3.在jar包代码中使用:InputStream inputStream = this.getClass().getResourceAsStream(path) 的写法,不管路径以是否以 / 开始,都是从jar包内部的根目录为起点。
以下是测试代码,代码的最终运行结果是(jar包放在/opt/test/目录进行运行):
1.在/opt/pathTest/文件夹下新建了 test_absolutePath.txt文件
2.在/opt/test/pathTest/文件夹下新建了 test_relativePath.txt 文件
3.成功从/opt/test/test.jar/pathTest/test_injarPath.txt文件中读取出内容
4.和3结果一样
import java.io.File;
import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.net.DatagramSocket; import java.net.InetSocketAddress; import java.net.ServerSocket; import java.net.Socket; import java.util.concurrent.TimeUnit; import javax.net.ssl.HttpsURLConnection; import javax.print.attribute.standard.Severity; import com.sun.tools.classfile.Annotation.element_value; import com.sun.tools.internal.xjc.reader.xmlschema.bindinfo.BIConversion.Static; public class Test { public static void main(String args[]) throws IOException { new Test().testPath(); } public void testPath(){ try { String path1 = "/opt/pathTest/"; File file = new File(path1); if(!file.exists()){ file.mkdirs(); } FileOutputStream fos = new FileOutputStream(path1+"test_absolutePath.txt"); fos.write("hahahhaha".getBytes()); fos.close(); String path2 = "pathTest/"; File file2 = new File(path2); if(!file2.exists()){ file2.mkdirs(); } FileOutputStream fos2 = new FileOutputStream(path2+"test_relativePath.txt"); fos2.write("hahahhaha".getBytes()); fos2.close(); //jar包内部用读取来测试 String path3 = "/pathTest/test_injarPath.txt"; InputStream inputStream = this.getClass().getResourceAsStream(path3); byte[] buffer = new byte[1024]; int n = inputStream.read(buffer); System.out.println("form file:" + path3 + " read:" + new String(buffer,0,n)); inputStream.close(); //jar包内部用读取来测试 String path4 = "pathTest/test_injarPath.txt"; inputStream = this.getClass().getResourceAsStream(path4); buffer = new byte[1024]; n = inputStream.read(buffer); System.out.println("form file:" + path4 + " read:" + new String(buffer,0,n)); inputStream.close(); } catch (Exception e) { e.printStackTrace(); } } }