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Java VTD-XML找不到符号错误。如何在编译java时正确引用包?_Java_Xml_Vtd Xml - Fatal编程技术网

Java VTD-XML找不到符号错误。如何在编译java时正确引用包?

Java VTD-XML找不到符号错误。如何在编译java时正确引用包?,java,xml,vtd-xml,Java,Xml,Vtd Xml,我不是Java程序员,但需要编写一个Java程序来解析一个大的(400mb)xml文件。我选择了vtd xml,但不知道如何正确引用该包。我不想使用maven/gradle,因为我不经常用Java编程,只需要引用这个包。我有: import com.ximpleware.*; 在我的java文件的顶部。我将vtd xml源代码保存在与java文件相同的目录中,因此目录结构如下所示: my_java.java vtd_xml/com vtd_xml/example vtd_xml/install

我不是Java程序员,但需要编写一个Java程序来解析一个大的(400mb)xml文件。我选择了vtd xml,但不知道如何正确引用该包。我不想使用maven/gradle,因为我不经常用Java编程,只需要引用这个包。我有:

import com.ximpleware.*;
在我的java文件的顶部。我将vtd xml源代码保存在与java文件相同的目录中,因此目录结构如下所示:

my_java.java
vtd_xml/com
vtd_xml/example
vtd_xml/install.txt  
vtd_xml/Readme.txt   
vtd_xml/ximpleware_2.12-java-light.zip
vtd_xml/vtd-xml_light-2-12.jar
zephyr_4.java:8: error: cannot find symbol
import com.ximpleware.VTDGen;
                 ^
  symbol:   class VTDGen
  location: package com.ximpleware
zephyr_4.java:10: error: cannot find symbol
import com.ximpleware.AutoPilot;
                 ^
  symbol:   class AutoPilot
  location: package com.ximpleware
 zephyr_4.java:11: error: cannot find symbol
import com.ximpleware.XMLModifier;
                 ^
  symbol:   class XMLModifier
  location: package com.ximpleware
zephyr_4.java:16: error: cannot find symbol
      public static void main(String argv[]) throws NavException,      IOException{
                                                ^
  symbol:   class NavException
  location: class zephyr_4
zephyr_4.java:18: error: cannot find symbol
            VTDGen vg = new VTDGen();
            ^
  symbol:   class VTDGen
  location: class zephyr_4
zephyr_4.java:18: error: cannot find symbol
            VTDGen vg = new VTDGen();
                        ^
  symbol:   class VTDGen
  location: class zephyr_4
zephyr_4.java:21: error: cannot find symbol
                AutoPilot ap = new AutoPilot(vn);
                ^
  symbol:   class AutoPilot
  location: class zephyr_4
zephyr_4.java:21: error: cannot find symbol
                AutoPilot ap = new AutoPilot(vn);
                               ^
  symbol:   class AutoPilot
  location: class zephyr_4
zephyr_4.java:22: error: cannot find symbol
                XMLModifier xm = new XMLModifier(vn);
                ^
  symbol:   class XMLModifier
  location: class zephyr_4
zephyr_4.java:22: error: cannot find symbol
                XMLModifier xm = new XMLModifier(vn);
                                     ^
  symbol:   class XMLModifier
  location: class zephyr_4
10 errors
我导出了类路径,以便

echo $CLASSPATH
返回

vtd_xml/vtd-xml_light-2-12.jar
但是当我编译java文件时

javac my_java.java
我遇到以下(令人沮丧的)错误:

我做错了什么?以下是我的源代码,以备不时之需:

import java.io.*; 
import com.ximpleware.*;
import java.util.*;

public class my_java {
      public static void main(String argv[]) throws NavException, IOException{
            // open a file and read the content into a byte array
            VTDGen vg = new VTDGen();
            if (vg.parseFile("pubmed_result.xml", true)){
                VTDNav vn = vg.getNav();
                AutoPilot ap = new AutoPilot(vn);
                XMLModifier xm = new XMLModifier(vn);
                String query = "count(//PubmedArticleSet/PubmedArticle"
                   + "/MedlineCitation/Article"
                   + "/AuthorList/Author[contains(LastName,\"Sangani\") and "
                   + "contains(ForeName, \"Rahul G\")])";
                ap.selectXPath(query);
                ap.bind(vn);


                int i = -1;
                while((i=ap.evalXPathToNumber())!=-1){
                    System.out.println(vn.toNormalizedPathString()); 
                }
            }
      }
}
更新我的符号错误看起来仍然像:

my_java.java
vtd_xml/com
vtd_xml/example
vtd_xml/install.txt  
vtd_xml/Readme.txt   
vtd_xml/ximpleware_2.12-java-light.zip
vtd_xml/vtd-xml_light-2-12.jar
zephyr_4.java:8: error: cannot find symbol
import com.ximpleware.VTDGen;
                 ^
  symbol:   class VTDGen
  location: package com.ximpleware
zephyr_4.java:10: error: cannot find symbol
import com.ximpleware.AutoPilot;
                 ^
  symbol:   class AutoPilot
  location: package com.ximpleware
 zephyr_4.java:11: error: cannot find symbol
import com.ximpleware.XMLModifier;
                 ^
  symbol:   class XMLModifier
  location: package com.ximpleware
zephyr_4.java:16: error: cannot find symbol
      public static void main(String argv[]) throws NavException,      IOException{
                                                ^
  symbol:   class NavException
  location: class zephyr_4
zephyr_4.java:18: error: cannot find symbol
            VTDGen vg = new VTDGen();
            ^
  symbol:   class VTDGen
  location: class zephyr_4
zephyr_4.java:18: error: cannot find symbol
            VTDGen vg = new VTDGen();
                        ^
  symbol:   class VTDGen
  location: class zephyr_4
zephyr_4.java:21: error: cannot find symbol
                AutoPilot ap = new AutoPilot(vn);
                ^
  symbol:   class AutoPilot
  location: class zephyr_4
zephyr_4.java:21: error: cannot find symbol
                AutoPilot ap = new AutoPilot(vn);
                               ^
  symbol:   class AutoPilot
  location: class zephyr_4
zephyr_4.java:22: error: cannot find symbol
                XMLModifier xm = new XMLModifier(vn);
                ^
  symbol:   class XMLModifier
  location: class zephyr_4
zephyr_4.java:22: error: cannot find symbol
                XMLModifier xm = new XMLModifier(vn);
                                     ^
  symbol:   class XMLModifier
  location: class zephyr_4
10 errors

您需要返回vtd xml网站并下载vtd xml的标准版。。。要解释这一点:

实际上有3个vtd xml版本:

---轻巧的一款是为移动设备设计的裸骨解析器 ---standard是功能最强大/功能最丰富、最完整的一款 ---扩展版功能较少,但支持高达256 gb的文档

所以你要找的是标准版,我想

这里是链接

您的代码中有一个小错误

ap.evalXPathToNumber返回一个double,而不是节点集,因此您可以直接分配返回的结果并使用它。。。虽然循环不必要


另一个建议是,可以打开VTDGen的vg.setLCLevel(5),这可能有助于提高xpath性能…

Ok。我下载了这个文件,但我仍然得到相同的“找不到符号错误”。我导出了我的类路径以引用jar文件(我在Linux机器上),但我一定是做错了什么。。。知道它可能是什么吗?类路径是正确的。jvm的版本是1.7.0.101。我在一台linux机器上。vtd xml代码在运行之前必须编译吗?当然不是。。。你删除了类路径的旧引用了吗?另一件要检查的事情是确保你的类路径是全局的。。。不是本地的,你能给我看一下符号错误的脚本吗?