导入org.apache.oro无法解析

Question

我试图使用FTPClient读取文件名。 我使用过commons-net-3.3.jar和commons-io-2.4.jar。 但在执行时，我得到以下例外，

Exception in thread "main" java.lang.Error: Unresolved compilation problems: 
The import org.apache.oro cannot be resolved
The import org.apache.oro cannot be resolved
The import org.apache.oro cannot be resolved
The import org.apache.oro cannot be resolved
The import org.apache.oro cannot be resolved
The import org.apache.oro cannot be resolved
Pattern cannot be resolved to a type
MatchResult cannot be resolved to a type
PatternMatcher cannot be resolved to a type
_matcher_ cannot be resolved
Perl5Matcher cannot be resolved to a type
pattern cannot be resolved
Perl5Compiler cannot be resolved to a type
MalformedPatternException cannot be resolved to a type
result cannot be resolved or is not a field
_matcher_ cannot be resolved
pattern cannot be resolved or is not a field
result cannot be resolved or is not a field
_matcher_ cannot be resolved
result cannot be resolved or is not a field
result cannot be resolved or is not a field
result cannot be resolved or is not a field
result cannot be resolved or is not a field
result cannot be resolved or is not a field
result cannot be resolved or is not a field
result cannot be resolved or is not a field



at org.apache.commons.net.ftp.parser.RegexFTPFileEntryParserImpl.<init>(RegexFTPFileEntryParserImpl.java:19)
at org.apache.commons.net.ftp.parser.ConfigurableFTPFileEntryParserImpl.<init>(ConfigurableFTPFileEntryParserImpl.java:57)
at org.apache.commons.net.ftp.parser.UnixFTPEntryParser.<init>(UnixFTPEntryParser.java:136)
at org.apache.commons.net.ftp.parser.UnixFTPEntryParser.<init>(UnixFTPEntryParser.java:119)
at org.apache.commons.net.ftp.parser.DefaultFTPFileEntryParserFactory.createUnixFTPEntryParser(DefaultFTPFileEntryParserFactory.java:169)
at org.apache.commons.net.ftp.parser.DefaultFTPFileEntryParserFactory.createFileEntryParser(DefaultFTPFileEntryParserFactory.java:94)
at org.apache.commons.net.ftp.FTPClient.initiateListParsing(FTPClient.java:2359)
at org.apache.commons.net.ftp.FTPClient.listFiles(FTPClient.java:2142)
at org.apache.commons.net.ftp.FTPClient.listFiles(FTPClient.java:2188)
at com.school.util.GetFileList.main(GetFileList.java:32)

Answer 1

看起来你有一个旧版本的commons-net，它依赖于类路径中的Jakarta ORO。 Commons-net过去依赖ORO直到版本1.4.1 。
如果您使用的是Maven / Gradle / Ivy，请确保您没有将此版本作为传递依赖项或其他库。
丢弃旧版本的commons-net应该可以解决问题。