I am looking for removing foo parameter and its value from all the possible following query strings in Java.
Is there a regex pattern to do this?
http://localhost/test?foo=abc&foobar=def
http://localhost/test?foobar=def&foo=abc
http://localhost/test?foo=abc
http://localhost/test?foobar=def&foo=abc&foobar2=def
The resulting strings would be
http://localhost/test?foobar=def
http://localhost/test?foobar=def
http://localhost/test
http://localhost/test?foobar=def&foobar2=def
This regex should match the GET param and its value...
(?<=[?&;])foo=.*?($|[&;])
RegExr.
Just replace it with an empty string.
For reference, there is a better (Perl) regex available in this other question: Regular expression to remove one parameter from query string
In Java, this can be implemented as follows:
public static String removeParams(String queryString, String... params) {
for (String param : params) {
String keyValue = param + "=[^&]*?";
queryString = queryString.replaceAll("(&" + keyValue + "(?=(&|$))|^" + keyValue + "(&|$))", "");
}
return queryString;
}
This is an extension of the answer provided by mchr.
It allows params to be removed from an url and from a query string, and shows how to execute the javascript test cases he mentions. Since it uses a regex, it will return the url with all the other parameters exactly where they were before. This is useful if you want to remove some parameters from an url when "signing" an url ;-) Note that this does not remove any completely empty parameters.
e.g. it will not remove foo from /test?foo&me=52
The test cases listed below remove the parameters, "foo" and "test" when found in the query string.
You can test it out line here at Repl.it
class Main {
public static void main(String[] args) {
runTests();
}
public static void runTests() {
test("foo=%2F{}/me/you&me=52", "me=52");
test("?foo=%2F{}/me/you&me=52", "?me=52");
test("?foo=52&me=able was i ere&test=2", "?me=able was i ere");
test("foo=", "");
test("?", "");
test("?foo=52", "");
test("test?", "test");
test("test?foo=23", "test");
test("foo=&bar=456", "bar=456");
test("bar=456&foo=", "bar=456");
test("abc=789&foo=&bar=456", "abc=789&bar=456");
test("foo=123", "");
test("foo=123&bar=456", "bar=456");
test("bar=456&foo=123", "bar=456");
test("abc=789&foo=123&bar=456", "abc=789&bar=456");
test("xfoo", "xfoo");
test("xfoo&bar=456", "xfoo&bar=456");
test("bar=456&xfoo", "bar=456&xfoo");
test("abc=789&xfoo&bar=456", "abc=789&xfoo&bar=456");
test("xfoo=", "xfoo=");
test("xfoo=&bar=456", "xfoo=&bar=456");
test("bar=456&xfoo=", "bar=456&xfoo=");
test("abc=789&xfoo=&bar=456", "abc=789&xfoo=&bar=456");
test("xfoo=123", "xfoo=123");
test("xfoo=123&bar=456", "xfoo=123&bar=456");
test("bar=456&xfoo=123", "bar=456&xfoo=123");
test("abc=789&xfoo=123&bar=456", "abc=789&xfoo=123&bar=456");
test("foox", "foox");
test("foox&bar=456", "foox&bar=456");
test("bar=456&foox", "bar=456&foox");
test("abc=789&foox&bar=456", "abc=789&foox&bar=456");
test("foox=", "foox=");
test("foox=&bar=456", "foox=&bar=456");
test("bar=456&foox=", "bar=456&foox=");
test("abc=789&foox=&bar=456", "abc=789&foox=&bar=456");
test("foox=123", "foox=123");
test("foox=123&bar=456", "foox=123&bar=456");
test("bar=456&foox=123", "bar=456&foox=123");
test("abc=789&foox=123&bar=456", "abc=789&foox=123&bar=456");
}
public static void test (String input, String expected) {
String result = removeParamsFromUrl(input, "foo", "test");
if (! result.equals(expected))
throw new RuntimeException("Failed:" + input);
System.out.println("Passed:" + input + ", output:" + result);
}
public static String removeParamsFromQueryString(String queryString, String... params) {
for (String param : params) {
String keyValue = param + "=[^&]*?";
queryString = queryString.replaceAll("(&" + keyValue + "(?=(&|$))|^" + keyValue + "(&|$))", "");
}
return queryString;
}
public static String removeParamsFromUrl(String url, String... params) {
String queryString;
String baseUrl;
int index = url.indexOf("?");
boolean wasFullUrl = (index != -1);
if (wasFullUrl)
{
baseUrl = url.substring(0, index);
queryString = url.substring(index+1);
}
else
{
baseUrl = "";
queryString = url;
}
String newQueryString = removeParamsFromQueryString(queryString, params);
String result;
if (wasFullUrl)
{
boolean isEmpty = newQueryString == null || newQueryString.equals("");
result = isEmpty ? baseUrl : baseUrl + "?" + newQueryString;
}
else
{
result = newQueryString;
}
return result;
}
}
url=url.replaceAll("(&"+param+"=[^&]*\$)|(\\?"+param+"=[^&]*\$)|("+param+"=[^&]*&)","")
Related
I have a Decoded URL String that is created dynamically that is in the following form.
field1==Z;field2==abc;field3==000;field4==100000154;field5==XLPO;field6==Z3&limit=2
I want to be able to dynamically pass in a key and obtain its relavent value. Say if we pass in "field2" then we should get "abc".
Example:
public class ComplexQueryParamProcessor {
public static void main(String[] args) {
String URL = "field1==Z;field2==abc;field3==000;field4==100000154;field5==XLPO;field6==Z3&limit=2";
String value = getValueFromURLString(URL, "field4"); // should return "100000154"
System.out.println(value);
}
public static String getValueFromURLString (String URL, String key){
String value = null;
//do something and extract "value" of "key" from URL
return value;
}
}
Any help would be greatly appreciated.
Thanks to schred I was able to figure it out using a combination of indexOf() and split()
public static String getValueFromURLString (String URL, String key){
String value = null;
//do something and extract "value" of "key" from URL
int index = URL.indexOf(key);
String s1 = URL.substring(index, URL.length());
String s2 = s1.split(";" , 2)[0];
value = s2.split("==", 2)[1];
return value;
}
I have a URL and I need to get the value of v from this URL.
Here is my URL: http://www.youtube.com/watch?v=_RCIP6OrQrE
How can I do that?
I think the one of the easiest ways out would be to parse the string returned by URL.getQuery() as
public static Map<String, String> getQueryMap(String query) {
String[] params = query.split("&");
Map<String, String> map = new HashMap<String, String>();
for (String param : params) {
String name = param.split("=")[0];
String value = param.split("=")[1];
map.put(name, value);
}
return map;
}
You can use the map returned by this function to retrieve the value keying in the parameter name.
If you're on Android, you can do this:
Uri uri = Uri.parse(url);
String v = uri.getQueryParameter("v");
I have something like this:
import org.apache.http.NameValuePair;
import org.apache.http.client.utils.URIBuilder;
private String getParamValue(String link, String paramName) throws URISyntaxException {
List<NameValuePair> queryParams = new URIBuilder(link).getQueryParams();
return queryParams.stream()
.filter(param -> param.getName().equalsIgnoreCase(paramName))
.map(NameValuePair::getValue)
.findFirst()
.orElse("");
}
I wrote this last month for Joomla Module when implementing youtube videos (with the Gdata API). I've since converted it to java.
Import These Libraries
import java.net.URL;
import java.util.regex.*;
Copy/Paste this function
public String getVideoId( String videoId ) throws Exception {
String pattern = "^(https?|ftp|file)://[-a-zA-Z0-9+&##/%?=~_|!:,.;]*[-a-zA-Z0-9+&##/%=~_|]";
Pattern p = Pattern.compile(pattern);
Matcher m = p.matcher(videoId);
int youtu = videoId.indexOf("youtu");
if(m.matches() && youtu != -1){
int ytu = videoId.indexOf("http://youtu.be/");
if(ytu != -1) {
String[] split = videoId.split(".be/");
return split[1];
}
URL youtube = new URL(videoId);
String[] split = youtube.getQuery().split("=");
int query = split[1].indexOf("&");
if(query != -1){
String[] nSplit = split[1].split("&");
return nSplit[0];
} else return split[1];
}
return null; //throw something or return what you want
}
URL's it will work with
http://www.youtube.com/watch?v=k0BWlvnBmIE (General URL)
http://youtu.be/k0BWlvnBmIE (Share URL)
http://www.youtube.com/watch?v=UWb5Qc-fBvk&list=FLzH5IF4Lwgv-DM3CupM3Zog&index=2 (Playlist URL)
Import these libraries
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
Similar to the verisimilitude, but with the capabilities of handling multivalue parameters. Note: I've seen HTTP GET requests without a value, in this case the value will be null.
public static List<NameValuePair> getQueryMap(String query)
{
List<NameValuePair> queryMap = new ArrayList<NameValuePair>();
String[] params = query.split(Pattern.quote("&"));
for (String param : params)
{
String[] chunks = param.split(Pattern.quote("="));
String name = chunks[0], value = null;
if(chunks.length > 1) {
value = chunks[1];
}
queryMap.add(new BasicNameValuePair(name, value));
}
return queryMap;
}
Example:
GET /bottom.gif?e235c08=1509896923&%49%6E%...
Using pure Java 8
Assumming you want to extract param "v" from url:
String paramV = Stream.of(url.split("?")[1].split("&"))
.map(kv -> kv.split("="))
.filter(kv -> "v".equalsIgnoreCase(kv[0]))
.map(kv -> kv[1])
.findFirst()
.orElse("");
Assuming the URL syntax will always be http://www.youtube.com/watch?v= ...
String v = "http://www.youtube.com/watch?v=_RCIP6OrQrE".substring(31);
or disregarding the prefix syntax:
String url = "http://www.youtube.com/watch?v=_RCIP6OrQrE";
String v = url.substring(url.indexOf("v=") + 2);
I believe we have a better approach to answer this question.
1: Define a function that returns Map values.
Here we go.
public Map<String, String> getUrlValues(String url) throws UnsupportedEncodingException {
int i = url.indexOf("?");
Map<String, String> paramsMap = new HashMap<>();
if (i > -1) {
String searchURL = url.substring(url.indexOf("?") + 1);
String params[] = searchURL.split("&");
for (String param : params) {
String temp[] = param.split("=");
paramsMap.put(temp[0], java.net.URLDecoder.decode(temp[1], "UTF-8"));
}
}
return paramsMap;
}
2: Call your function surrounding with a try catch block
Here we go
try {
Map<String, String> values = getUrlValues("https://example.com/index.php?form_id=9&page=1&view_id=78");
String formId = values.get("form_id");
String page = values.get("page");
String viewId = values.get("view_id");
Log.d("FormID", formId);
Log.d("Page", page);
Log.d("ViewID", viewId);
} catch (UnsupportedEncodingException e) {
Log.e("Error", e.getMessage());
}
If you are using Jersey (which I was, my server component needs to make outbound HTTP requests) it contains the following public method:
var multiValueMap = UriComponent.decodeQuery(uri, true);
It is part of org.glassfish.jersey.uri.UriComponent, and the javadoc is here. Whilst you may not want all of Jersey, it is part of the Jersey common package which isn't too bad on dependencies...
I solved the problem like this
public static String getUrlParameterValue(String url, String paramName) {
String value = "";
List<NameValuePair> result = null;
try {
result = URLEncodedUtils.parse(new URI(url), UTF_8);
value = result.stream().filter(pair -> pair.getName().equals(paramName)).findFirst().get().getValue();
System.out.println("--------------> \n" + paramName + " : " + value + "\n");
} catch (URISyntaxException e) {
e.printStackTrace();
}
return value;
}
this will work for all sort of youtube url :
if url could be
youtube.com/?v=_RCIP6OrQrE
youtube.com/v/_RCIP6OrQrE
youtube.com/watch?v=_RCIP6OrQrE
youtube.com/watch?v=_RCIP6OrQrE&feature=whatever&this=that
Pattern p = Pattern.compile("http.*\\?v=([a-zA-Z0-9_\\-]+)(?:&.)*");
String url = "http://www.youtube.com/watch?v=_RCIP6OrQrE";
Matcher m = p.matcher(url.trim()); //trim to remove leading and trailing space if any
if (m.matches()) {
url = m.group(1);
}
System.out.println(url);
this will extract video id from your url
further reference
My solution mayble not good
String url = "https://www.youtube.com/watch?param=test&v=XcHJMiSy_1c&lis=test";
int start = url.indexOf("v=")+2;
// int start = url.indexOf("list=")+5; **5 is length of ("list=")**
int end = url.indexOf("&", start);
end = (end == -1 ? url.length() : end);
System.out.println(url.substring(start, end));
// result: XcHJMiSy_1c
work fine with:
https://www.youtube.com/watch?param=test&v=XcHJMiSy_1c&lis=test
https://www.youtube.com/watch?v=XcHJMiSy_1c
public static String getQueryMap(String query) {
String[] params = query.split("&");
for (String param : params) {
String name = param.split("=")[0];
if ("YourParam".equals(name)) {
return param.split("=")[1];
}
}
return null;
}
I have a String containing a URL. I want to get just one piece of data out of it: an int that should be showing up in the query string.
So if the url is:
http://domain.tld/page.html?iVar=123
I want to get "123" into an int.
What's the most elegant way you know to do this?
You could try matching just that parameter in the URL string:
public static Integer getIVarParamValue(String urlStr) {
Pattern p = Pattern.compile("iVar=(\\d+)");
Matcher m = p.matcher(urlStr);
if (m.find()) {
return Integer.parseInt(m.group(1));
}
return null;
}
It seems you want to obtain get parameters and parse them. I have this method here (got it from somewhere on SO, I guess):
public static Map<String, List<String>> getQueryParams(String url) {
try {
Map<String, List<String>> params = new HashMap<String, List<String>>();
String[] urlParts = url.split("\\?");
if (urlParts.length > 1) {
String query = urlParts[1];
for (String param : query.split("&")) {
String[] pair = param.split("=");
String key = URLDecoder.decode(pair[0], "UTF-8");
String value = "";
if (pair.length > 1) {
value = URLDecoder.decode(pair[1], "UTF-8");
}
List<String> values = params.get(key);
if (values == null) {
values = new ArrayList<String>();
params.put(key, values);
}
values.add(value);
}
}
return params;
} catch (UnsupportedEncodingException ex) {
throw new AssertionError(ex);
}
}
So:
String var = WebUtils.getQueryParams(url).get("iVar");
int intVar = Integer.parseInt(var);
You can use the URL class.
i.e.:
URL myUrl = new URL("http://domain.tld/page.html?iVar=123");
String query = myUrl.getQuery(); //this will return iVar=123
//at this point you can either parse it manually (i.e. use some of the regexp in the other suggestions, or use something like:
String[] parts = query.split();
String variable = parts[0];
String value = parts[1];
This will work only for this case though and won't work if you have additional params or no params.
There are a number of solution that will split it into a param map online, you can see some here.
If it's really as simple as you describe: There is only 1 int in your URL and all you want is that int, I'd go for a regular expression. If it is actually more complicated see the other answers.
Pattern p = Pattern.compile("[0-9]+");
Matcher m = p.matcher("http://domain.tld/page.html?iVar=123");
if (m.find())
System.out.println(m.group());
This also could do the work :
public static int getIntParam(HttpServletRequest request, String name, int defaultValue) {
String value = request.getParameter(name);
try {
if (value != null) {
return Integer.valueOf(value);
}
} catch (NumberFormatException e) {
}
return defaultValue;
}
Hope it helps!
If the query string part of the URL is always the same (so if it was always iVar) you could use urlAsString.indexOf("iVar=") to find iVar= and then knowing the number is after that, extract the number. That is admittedly not the least brittle approach.
But if you're looking for all the query strings then Bozho's answer is much better.
Does anyone have, or know of, a java class that I can use to manipulate query strings?
Essentially I'd like a class that I can simply give a query string to and then delete, add and modify query string KVP's.
Thanks in advance.
EDIT
In response to a comment made to this question, the query string will look something like this;
N=123+456+112&Ntt=koala&D=abc
So I'd like to pass this class the query string and say something like;
String[] N = queryStringClass.getParameter("N");
and then maybe
queryStringClass.setParameter("N", N);
and maybe queryStringClass.removeParameter("N");
Or something to that effect.
SOmething like this
public static Map<String, String> getQueryMap(String query)
{
String[] params = query.split("&");
Map<String, String> map = new HashMap<String, String>();
for (String param : params)
{
String name = param.split("=")[0];
String value = param.split("=")[1];
map.put(name, value);
}
return map;
}
To iterate the map simply:
String query = url.getQuery();
Map<String, String> map = getQueryMap(query);
Set<String> keys = map.keySet();
for (String key : keys)
{
System.out.println("Name=" + key);
System.out.println("Value=" + map.get(key));
}
You can also use Google Guava's Splitter.
String queryString = "variableA=89&variableB=100";
Map<String,String> queryParameters = Splitter
.on("&")
.withKeyValueSeparator("=")
.split(queryString);
System.out.println(queryParameters.get("variableA"));
prints out
89
This I think is a very readable alternative to parsing it yourself.
Edit: As #raulk pointed out, this solution does not account for escaped characters. However, this may not be an issue because before you URL-Decode, the query string is guaranteed to not have any escaped characters that conflict with '=' and '&'. You can use this to your advantage in the following way.
Say that you must decode the following query string:
a=%26%23%25!)%23(%40!&b=%23%24(%40)%24%40%40))%24%23%5E*%26
which is URL encoded, then you are guaranteed that the '&' and '=' are specifically used for separating pairs and key from value, respectively, at which point you can use the Guava splitter to get:
a = %26%23%25!)%23(%40!
b = %23%24(%40)%24%40%40))%24%23%5E*%26
Once you have obtained the key-value pairs, then you can URL decode them separately.
a = &#%!)#(#!
b = #$(#)$##))$#^*&
That should cover all cases.
If you are using J2EE, you can use ServletRequest.getParameterValues().
Otherwise, I don't think Java has any common classes for query string handling. Writing your own shouldn't be too hard, though there are certain tricky edge cases, such as realizing that technically the same key may appear more than once in the query string.
One implementation might look like:
import java.util.*;
import java.net.URLEncoder;
import java.net.URLDecoder;
public class QueryParams {
private static class KVP {
final String key;
final String value;
KVP (String key, String value) {
this.key = key;
this.value = value;
}
}
List<KVP> query = new ArrayList<KVP>();
public QueryParams(String queryString) {
parse(queryString);
}
public QueryParams() {
}
public void addParam(String key, String value) {
if (key == null || value == null)
throw new NullPointerException("null parameter key or value");
query.add(new KVP(key, value));
}
private void parse(String queryString) {
for (String pair : queryString.split("&")) {
int eq = pair.indexOf("=");
if (eq < 0) {
// key with no value
addParam(URLDecoder.decode(pair), "");
} else {
// key=value
String key = URLDecoder.decode(pair.substring(0, eq));
String value = URLDecoder.decode(pair.substring(eq + 1));
query.add(new KVP(key, value));
}
}
}
public String toQueryString() {
StringBuilder sb = new StringBuilder();
for (KVP kvp : query) {
if (sb.length() > 0) {
sb.append('&');
}
sb.append(URLEncoder.encode(kvp.key));
if (!kvp.value.equals("")) {
sb.append('=');
sb.append(URLEncoder.encode(kvp.value));
}
}
return sb.toString();
}
public String getParameter(String key) {
for (KVP kvp : query) {
if (kvp.key.equals(key)) {
return kvp.value;
}
}
return null;
}
public List<String> getParameterValues(String key) {
List<String> list = new LinkedList<String>();
for (KVP kvp : query) {
if (kvp.key.equals(key)) {
list.add(kvp.value);
}
}
return list;
}
public static void main(String[] args) {
QueryParams qp = new QueryParams("k1=v1&k2&k3=v3&k1=v4&k1&k5=hello+%22world");
System.out.println("getParameter:");
String[] keys = new String[] { "k1", "k2", "k3", "k5" };
for (String key : keys) {
System.out.println(key + ": " + qp.getParameter(key));
}
System.out.println("getParameters(k1): " + qp.getParameterValues("k1"));
}
}
Another way is to use apache http-components. It's a bit hacky, but at least you leverage all the parsing corner cases:
List<NameValuePair> params =
URLEncodedUtils.parse("http://example.com/?" + queryString, Charset.forName("UTF-8"));
That'll give you a List of NameValuePair objects that should be easy to work with.
You can create a util method and use regular expression to parse it. A pattern like "[;&]" should suffice.
I am new to eclipse plugin development and I am trying to convert a IMethod to a string representation of the full method name. I.E.
my.full.package.ClassName.methodName(int param, String string)
so far I have had to hand roll my own solution. Is there a better way?
private static String getMethodFullName(IMethod iMethod)
{
String packageString = "[Default Package]";
try {
IPackageDeclaration[] declarations = iMethod.getCompilationUnit().getPackageDeclarations();
if(declarations.length > 0)
{
packageString = declarations[0].getElementName();
}
} catch (JavaModelException e) {
}
String classString = iMethod.getCompilationUnit().getElementName();
classString = classString.replaceAll(".java", "");
String methodString = iMethod.getElementName() + "(";
for (String type : iMethod.getParameterTypes()) {
methodString += type + ",";
}
methodString += ")";
return packageString + "." + classString + "." + methodString;
}
You can get the Fully qualified name for the type using
method.getDeclaringType().getFullyQualifiedName();
This is probably easier than accessing the package from the compilation unit. The rest of you function looks correct.
One small point: you should use StringBuilder to build up the string instead of adding to a standard String. Strings are immutable so addition creates loads of unrecesary temparary objects.
private static String getMethodFullName(IMethod iMethod)
{
StringBuilder name = new StringBuilder();
name.append(iMethod.getDeclaringType().getFullyQualifiedName());
name.append(".");
name.append(iMethod.getElementName());
name.append("(");
String comma = "";
for (String type : iMethod.getParameterTypes()) {
name.append(comma);
comma = ", ";
name.append(type);
}
name.append(")");
return name.toString();
}
Thanks to iain and some more research I have come up with this solution. It seems like something like this should be built into the JDT....
import org.eclipse.jdt.core.Signature;
private static String getMethodFullName(IMethod iMethod)
{
StringBuilder name = new StringBuilder();
name.append(iMethod.getDeclaringType().getFullyQualifiedName());
name.append(".");
name.append(iMethod.getElementName());
name.append("(");
String comma = "";
String[] parameterTypes = iMethod.getParameterTypes();
try {
String[] parameterNames = iMethod.getParameterNames();
for (int i=0; i<iMethod.getParameterTypes().length; ++i) {
name.append(comma);
name.append(Signature.toString(parameterTypes[i]));
name.append(" ");
name.append(parameterNames[i]);
comma = ", ";
}
} catch (JavaModelException e) {
}
name.append(")");
return name.toString();
}
I am not sure it would take into account all cases (method within an internal class, an anonymous class, with generic parameters...)
When it comes to methods signatures, the classes to look into are:
org.eclipse.jdt.internal.corext.codemanipulation.AddUnimplementedMethodsOperation
org.eclipse.jdt.internal.corext.codemanipulation.StubUtility2
You need to get the jdt.core.dom.IMethodBinding, from which you can extract all what you need.
If you have a MethodInvocation, you can:
//MethodInvocation node
ITypeBinding type = node.getExpression().resolveTypeBinding();
IMethodBinding method=node.resolveMethodBinding();