这是一个简单的问题 - 给定两个URL,是否有内置方法或Apache库可以确定它们是否(逻辑上)相等?
例如,这两个URL是相等的:
http://stackoverflow.com
http://stackoverflow.com/
虽然URI.equals()
(以及存在问题的URL.equals()
)在这些特定示例中不会返回true
,但我认为这是可以假定等同性的唯一情况(因为HTTP协议中没有空路径)。
不能假定http://stackoverflow.com/foo
和http://stackoverflow.com/foo/
是等价的。
也许你可以使用URI.equals()
包装在一个实用程序方法中,明确处理这种特定情况。
URL urlOne = new URL("http://stackoverflow.com");
URL urlTwo = new URL("http://stackoverflow.com/");
if( urlOne.equals(urlTwo) )
{
// ....
}
文档提示 -
如果两个URL对象具有相同的协议、引用等效主机、在主机上具有相同的端口号以及文件和文件片段相同,则它们是相等的。
如果两个主机名都可以解析为相同的IP地址,则认为这两个主机等效;否则,如果任一主机名无法解析,则主机名必须相等,而不考虑大小写;或者两个主机名都等于null。
由于主机比较需要名称解析,因此此操作是阻塞操作。
注意:equals的定义行为已知与HTTP中的虚拟主机不一致。
因此,如@Joachim所建议的那样,您应该优先选择URI :: equals reference 。
URL.equals()
将会解析主机名!这不仅会在不期望的地方引入网络 IO,还会产生错误的结果(例如,如果它们托管在相同的 IP 上,则http://vhost1.com/
将等于http://vhost2.com/
!)。最好使用URI
并调用URI.equals()
。 - Joachim SauerURL.equals()
可能会产生不同/不一致的结果,这取决于您是否有互联网连接... - Tomasz Nurkiewicz您可以像这样测试它:
class Main {
public static void main(String[] args)
{
UrlComparer urlComparer = new UrlComparer();
expectResult(false, "key a case different", urlComparer.urlsMatch("//test.com?A=a&B=b", "//test.com?a=a&b=b"));
expectResult(false, "key a case different", urlComparer.urlsMatch("https://WWW.TEST.COM?A=1&b=2", "https://www.test.com?b=2&a=1"));
expectResult(false, "key a value different", urlComparer.urlsMatch("/test?a=2&A=A", "/test?a=A&a=2"));
expectResult(false, "key a value different", urlComparer.urlsMatch("https://WWW.TEST.COM?A=a&b=2", "https://www.test.com?b=2&A=1"));
expectResult(false, "null", urlComparer.urlsMatch("/test", null));
expectResult(false, "null", urlComparer.urlsMatch(null, "/test"));
expectResult(false, "port different", urlComparer.urlsMatch("//test.com:22?A=a&B=b", "//test.com:443?A=a&B=b"));
expectResult(false, "port different", urlComparer.urlsMatch("https://WWW.TEST.COM:8443", "https://www.test.com"));
expectResult(false, "protocol different", urlComparer.urlsMatch("http://WWW.TEST.COM:2121", "https://www.test.com:2121"));
expectResult(false, "protocol different", urlComparer.urlsMatch("http://WWW.TEST.COM?A=a&b=2", "https://www.test.com?b=2&A=a"));
expectResult(true, "both null", urlComparer.urlsMatch(null, null));
expectResult(true, "host and scheme different case", urlComparer.urlsMatch("HTTPS://WWW.TEST.COM", "https://www.test.com"));
expectResult(true, "host different case", urlComparer.urlsMatch("https://WWW.TEST.COM:443", "https://www.test.com"));
expectResult(true, "identical urls", urlComparer.urlsMatch("//test.com:443?A=a&B=b", "//test.com:443?A=a&B=b"));
expectResult(true, "identical urls", urlComparer.urlsMatch("/test?a=A&a=2", "/test?a=A&a=2"));
expectResult(true, "identical urls", urlComparer.urlsMatch("https://www.test.com", "https://www.test.com"));
expectResult(true, "parameter order changed", urlComparer.urlsMatch("https://www.test.com?a=1&b=2&c=522%2fMe", "https://www.test.com?c=522%2fMe&b=2&a=1"));
expectResult(true, "parmeter order changed", urlComparer.urlsMatch("https://WWW.TEST.COM?a=1&b=2", "https://www.test.com?b=2&a=1"));
}
public static void expectResult(boolean expectedResult, String msg, boolean result)
{
if (expectedResult != result)
throw new RuntimeException(msg);
}
}
UrlComparer.java
import java.net.URI;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.TreeMap;
import org.apache.http.NameValuePair;
import org.apache.http.client.utils.URLEncodedUtils;
public class UrlComparer
{
private boolean hostIsCaseSensitive = false;
private boolean pathIsCaseSensitive = true;
private boolean queryStringKeysAreCaseSensitive = true;
private boolean queryStringValuesAreCaseSensitive = false;
private boolean schemeIsCaseSensitive = false;
public boolean urlsMatch(String url1, String url2)
{
try
{
if (Objects.equals(url1, url2))
return true;
URI uri1 = new URI(url1);
URI uri2 = new URI(url2);
// Compare Query String Parameters
Map<String, String> mapParams1 = getQueryStringParams(uri1);
Map<String, String> mapParams2 = getQueryStringParams(uri2);
if (!mapsAreEqual(mapParams1, mapParams2, getQueryStringValuesAreCaseSensitive()))
return false;
// Compare scheme (http or https)
if (!stringsAreEqual(uri1.getScheme(), uri2.getScheme(), getSchemeIsCaseSensitive()))
return false;
// Compare host
if (!stringsAreEqual(uri1.getHost(), uri2.getHost(), getHostIsCaseSensitive()))
return false;
// Compare path
if (!stringsAreEqual(uri1.getPath(), uri2.getPath(), getPathIsCaseSensitive()))
return false;
// Compare ports
if (!portsAreEqual(uri1, uri2))
return false;
return true;
}
catch (Exception e)
{
return false;
}
}
protected Map<String, String> getQueryStringParams(URI uri)
{
Map<String, String> result = getListAsMap(URLEncodedUtils.parse(uri, "UTF-8"), getQueryStringKeysAreCaseSensitive());
return result;
}
protected boolean stringsAreEqual(String s1, String s2, boolean caseSensitive)
{
// Eliminate null cases
if (s1 == null || s2 == null)
{
if (s1 == s2)
return true;
return false;
}
if (caseSensitive)
{
return s1.equals(s2);
}
return s1.equalsIgnoreCase(s2);
}
protected boolean mapsAreEqual(Map<String, String> map1, Map<String, String> map2, boolean caseSensitiveValues)
{
for (Map.Entry<String, String> entry : map1.entrySet())
{
String key = entry.getKey();
String map1value = entry.getValue();
String map2value = map2.get(key);
if (!stringsAreEqual(map1value, map2value, caseSensitiveValues))
return false;
}
for (Map.Entry<String, String> entry : map2.entrySet())
{
String key = entry.getKey();
String map2value = entry.getValue();
String map1value = map2.get(key);
if (!stringsAreEqual(map1value, map2value, caseSensitiveValues))
return false;
}
return true;
}
protected boolean portsAreEqual(URI uri1, URI uri2)
{
int port1 = uri1.getPort();
int port2 = uri2.getPort();
if (port1 == port2)
return true;
if (port1 == -1)
{
String scheme1 = (uri1.getScheme() == null ? "http" : uri1.getScheme()).toLowerCase();
port1 = scheme1.equals("http") ? 80 : 443;
}
if (port2 == -1)
{
String scheme2 = (uri2.getScheme() == null ? "http" : uri2.getScheme()).toLowerCase();
port2 = scheme2.equals("http") ? 80 : 443;
}
boolean result = (port1 == port2);
return result;
}
protected Map<String, String> getListAsMap(List<NameValuePair> list, boolean caseSensitiveKeys)
{
Map<String, String> result;
if (caseSensitiveKeys)
{
result = new HashMap<String, String>();
}
else
{
result = new TreeMap<String, String>(String.CASE_INSENSITIVE_ORDER);
}
for (NameValuePair param : list)
{
if (caseSensitiveKeys)
{
if (!result.containsKey(param.getName()))
result.put(param.getName(), param.getValue());
}
else
{
result.put(param.getName(), param.getValue());
}
}
return result;
}
public boolean getSchemeIsCaseSensitive()
{
return schemeIsCaseSensitive;
}
public void setSchemeIsCaseSensitive(boolean schemeIsCaseSensitive)
{
this.schemeIsCaseSensitive = schemeIsCaseSensitive;
}
public boolean getHostIsCaseSensitive()
{
return hostIsCaseSensitive;
}
public void setHostIsCaseSensitive(boolean hostIsCaseSensitive)
{
this.hostIsCaseSensitive = hostIsCaseSensitive;
}
public boolean getPathIsCaseSensitive()
{
return pathIsCaseSensitive;
}
public void setPathIsCaseSensitive(boolean pathIsCaseSensitive)
{
this.pathIsCaseSensitive = pathIsCaseSensitive;
}
public boolean getQueryStringKeysAreCaseSensitive()
{
return queryStringKeysAreCaseSensitive;
}
public void setQueryStringKeysAreCaseSensitive(boolean queryStringKeysAreCaseSensitive)
{
this.queryStringKeysAreCaseSensitive = queryStringKeysAreCaseSensitive;
}
public boolean getQueryStringValuesAreCaseSensitive()
{
return queryStringValuesAreCaseSensitive;
}
public void setQueryStringValuesAreCaseSensitive(boolean queryStringValuesAreCaseSensitive)
{
this.queryStringValuesAreCaseSensitive = queryStringValuesAreCaseSensitive;
}
}
sameFile
public boolean sameFile(URL other)比较两个URL,
不包括片段组件。 如果此URL和其他参数相等而不考虑片段组件,则返回true。
参数: other - 要比较的URL。 返回值: 如果它们引用相同的远程对象,则为true;否则为false。
还请查看此链接
http://download.oracle.com/javase/6/docs/api/java/net/URL.html#sameFile(java.net.URL)
由于我无法添加评论,浏览器抛出了Javascript错误。所以我在这里添加了我的评论。对不便表示歉意。
//这是我建议的内容
>URL url1 = new URL("http://stackoverflow.com/foo");
>URL url2 = new URL("http://stackoverflow.com/foo/");
>System.out.println(url1.sameFile(url2));
// this is suggested by Joachim Sauer
>URI uri = new URI("http://stackoverflow.com/foo/");
>System.out.println(uri.equals("http://stackoverflow.com/foo"));
// Both are giving same result
所以 Joachim Sauer 再检查一次。
sameFile()
的文档中没有看到任何暗示它处理默认端口的内容(而且快速测试也不支持这种假设)。此外,sameFile()
也遭受了与URL.equals()
相同的问题,因为它也试图解析主机名。 - Joachim Sauerhttp://foo.googlecode.com/
和http://bar.googlecode.com/
)。 - Joachim Sauer