我在Ubuntu64 9.04
PC上安装了许多Java应用程序，但它们都无法解析域名（也有多个JRE，其中有些是IBM产品）。如果我将域名及其关联的IP地址放在hosts文件中，则Java应用程序仅适用于这些域。其他所有非Java程序（例如ping，firefox等）在域解析方面都可以正常工作。我尝试对java.security文件中的所有JRE禁用DNS缓存-
但这也不起作用。在解决这一问题上，我将不胜感激。谢谢！

更新：我确定我的家中或办公室中没有代理服务器。-非常感谢你们在这里帮助我。我真的要使用Linux而不是Windows，因为我再次进行Java开发。

jgreenwood@jeg-ubuntu64:~$ cat /etc/resolv.conf
# Generated by NetworkManager
domain hsd1.in.comcast.net.
search hsd1.in.comcast.net.
nameserver 192.168.0.1
jgreenwood@jeg-ubuntu64:~$ env | grep -i proxy
jgreenwood@jeg-ubuntu64:~$ dig google.com

; <<>> DiG 9.5.1-P2 <<>> google.com
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 56845
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;google.com.            IN  A

;; ANSWER SECTION:
google.com.     58  IN  A   74.125.53.100
google.com.     58  IN  A   74.125.45.100
google.com.     58  IN  A   74.125.67.100

;; Query time: 35 msec
;; SERVER: 192.168.0.1#53(192.168.0.1)
;; WHEN: Thu Oct 22 13:37:26 2009
;; MSG SIZE  rcvd: 76

更新：我用RAD编写了这个Java程序：

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.io.PrintWriter;
import java.io.StringWriter;

public class DomainResolutionTest {

    public static void main(String[] args) {
        if (args.length == 0) args = new String[] { "www.google.com" };

        try {
            InetAddress ip = InetAddress.getByName(args[0]);
            System.out.println(ip.toString());
        }catch (UnknownHostException uhx) {
            System.out.println("ERROR: " + uhx.getMessage() + "\n" + getStackTrace(uhx));
            Throwable cause = uhx.getCause();
            if (cause != null) System.out.println("CAUSE: " + cause.getMessage());
        }

    }

    public static String getStackTrace(Throwable t)
    {
        StringWriter sw = new StringWriter();
        PrintWriter pw = new PrintWriter(sw, true);
        t.printStackTrace(pw);
        pw.flush();
        sw.flush();
        return sw.toString();
    }

}

输出为：

ERROR: www.google.com
java.net.UnknownHostException: www.google.com
    at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
    at java.net.InetAddress$1.lookupAllHostAddr(InetAddress.java:862)
    at java.net.InetAddress.getAddressFromNameService(InetAddress.java:1213)
    at java.net.InetAddress.getAllByName0(InetAddress.java:1166)
    at java.net.InetAddress.getAllByName(InetAddress.java:1096)
    at java.net.InetAddress.getAllByName(InetAddress.java:1032)
    at java.net.InetAddress.getByName(InetAddress.java:982)
    at DomainResolutionTest.main(DomainResolutionTest.java:12)

从命令行：（相同的结果）

jgreenwood@jeg-ubuntu64:~$ javac DomainResolutionTest.java
jgreenwood@jeg-ubuntu64:~$ java DomainResolutionTest 
ERROR: www.google.com
java.net.UnknownHostException: www.google.com
    at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
    at java.net.InetAddress$1.lookupAllHostAddr(InetAddress.java:849)
    at java.net.InetAddress.getAddressFromNameService(InetAddress.java:1200)
    at java.net.InetAddress.getAllByName0(InetAddress.java:1153)
    at java.net.InetAddress.getAllByName(InetAddress.java:1083)
    at java.net.InetAddress.getAllByName(InetAddress.java:1019)
    at java.net.InetAddress.getByName(InetAddress.java:969)
    at DomainResolutionTest.main(DomainResolutionTest.java:12)
jgreenwood@jeg-ubuntu64:~$ java -version
java version "1.6.0_16"
Java(TM) SE Runtime Environment (build 1.6.0_16-b01)
Java HotSpot(TM) Server VM (build 14.2-b01, mixed mode)
jgreenwood@jeg-ubuntu64:~$