我的变量中有以下可能的值:URL,在 JAVA/JSP 中。
URL="http://a.b.com/Something?IDToken1=AppUser1"
URL="http://a.b.com/Something?IDToken1=AppUser1&variable1=value1"
URL="http://a.b.com/Something?IDToken1=AppUser1variable1=value1&variable2=value2"
URL="http://a.b.com/Something?variable1=value1&IDToken1=AppUser1"
URL="http://a.b.com/Something?variable1=value1&IDToken1=AppUser1&variable2=value2"
我正在尝试使用字符串或相关函数来查找可以编写哪些代码(一行或 2-5 行),这些函数可以为我提供一个名为“user=AppUser1”的变量,并且reConstructedURL=上述链接的任何值(如果 IDToken1 是传递给 URL 的唯一参数,则从中删除 IDToken1=AppUser1 后除外),否则,保留“?”字符并所有其他参数(+ 也不包括第一个 & 字符,即 reConstructedURL 变量中没有 & 字符/值作为结束字符)。我尝试了函数的子字符串和索引,但无法让它工作。
例如:
reConstructedURL="http://a.b.com/Something"
如果网址为:
URL =“http://a.b.com/Something?IDToken1=AppUser1”
reConstructedURL="http://a.b.com/Something?variable1=value1"
如果网址为:
URL="http://a.b.com/Something?IDToken1=AppUser1&variable1=value1"
reConstructedURL="http://a.b.com/Something?variable1=value1&variable2=value2"
如果网址为:
URL="http://a.b.com/Something?IDToken1=AppUser1&variable1=value1&variable2=value2"
reConstructedURL="http://a.b.com/Something?variable1=value1"
如果网址为:
URL="http://a.b.com/Something?variable1=value1&IDToken1=AppUser1"
reConstructedURL="http://a.b.com/Something?variable1=value1&variable2=value2"
如果网址为:
URL="http://a.b.com/Something?variable1=value1&IDToken1=AppUser1&variable2=value2"
这是我到目前为止所尝试过的。
public final String USER_VAR = "IDToken1";
public String[] extractNewURL(String currentGoToURL)
{
String[] userAndRetURL = new String[2];
//Sample incoming
//http://a.b.com/Something?IDToken1=Apptester2
//http://a.b.com/Something?IDToken1=Apptester2&variable2=100
//http://a.b.com/Something?variable1=Giga&IDToken1=Apptester2&variable2=100
try
{
String extractedUsername = "";
String[] stringArray = currentGoToURL.split(USER_VAR+"=");
String usernamePlusPlus = stringArray[1];
//Go up to the &
int firstAmp = usernamePlusPlus.indexOf('&');
if(firstAmp != -1)
{
extractedUsername = usernamePlusPlus.substring(0, firstAmp);
}
else
{
extractedUsername = usernamePlusPlus;
}
userAndRetURL[0] = extractedUsername;
//2nd part to reconstruct the URL
if(!"".equals(extractedUsername))
{
//TODO this needs to be smarter to pass along extra params
String[] splitURL = currentGoToURL.split("\\?");
String beginningURL = splitURL[0];
//System.err.println("BEG:"+beginningURL);
userAndRetURL[1] = beginningURL;
}
else
{
userAndRetURL[1] = currentGoToURL;
}
} catch (Exception e) {
//Ends up in catalina.out
System.err.println("EXCEPTION OCCURRED IN LOGIN.JSP: "+e.toString());
e.printStackTrace();
}
return userAndRetURL;
}
%>
<%
boolean weHaveUser = false;
String userNameCarryFwd = "DummyUser";
//App_USERNAME info is present in Headers
userNameCarryFwd = response.getHeader("App_USERNAME");
if (userNameCarryFwd == null)
{
userNameCarryFwd = request.getParameter("App_USERNAME");
if(userNameCarryFwd == null)
{
userNameCarryFwd = request.getParameter("IDToken1");
if(userNameCarryFwd == null)
{
//This is crazy but we are passing it on the URL to get around header not fwding
String somethingToParse = request.getParameter("goto");
String[] uAndURL = extractNewURL(somethingToParse);
userNameCarryFwd = uAndURL[0];
String nonEncoded = uAndURL[1];
//This will be after reconstructive surgery
gotoURL = viewBean.getEncodedInputValue(nonEncoded);
if(userNameCarryFwd == null)
userNameCarryFwd = "";
}
}
}
weHaveUser = (userNameCarryFwd == null || userNameCarryFwd.length() < 1) ? false : true;
我认为逻辑上得到它的最好方法是: 1. 从当前的“转到 URL”字符串中,如果我可以删除 IDToken=< value > 部分,并确保生成的“重定向 URL”字符串的结束字符不是以 < 结尾strong>? 或 & 即删除 ? 或 &(如果这是剥离后的最后一个字符 and)上述variable=value部分,如果存在?&或&&连续字符,则将其替换为?或& 字符,就可以了。
最佳答案
下面的代码可以帮助你。
public class URLResonstruction {
public static String reconstructURL(String url) {
int beginTknInx = url.indexOf("IDToken1");
// If there is no IDToken
if (beginTknInx < 0)
return url;
// If IDToken is only query parameter or IDToken is at end
int endTknInx = url.substring(beginTknInx).indexOf("&");
if (endTknInx < 0)
return url.substring(0, beginTknInx - 1);
// If IDToken is at beginning or in middle
String part1 = url.substring(0, beginTknInx);
String part2 = url.substring(beginTknInx + endTknInx);
return part1 + part2.substring(1, part2.length());
}
}
关于java - 如何提取/重组字符串值,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27994868/