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Split string into key-value pairs where a value can contain a delimiter

I am trying to split a string into key-value pairs which is very straight forward, but I realized very late that I don't have any validation on my input. the string can contain same delimiter that I am using to split. Not sure if this is possible but can someone please help find a way to split this string into a valid key/value pairs?
The current logic:
String key = "key1=value1,key2=value2,key3=value3,with,delimeter"
Map<String, String> map = new HashMap<>();
String[] entries = key.split(",");
for(String entry : entries) {
String[] keyValue = entry.split("=");
map.put(keyValue[0], keyValue[1]);
}
Expected output:
key1:value1
key2:value2
key3:value3,with,delimeter
But this code causes java.lang.ArrayIndexOutOfBoundsException as there are comma in the last value.
Note: I cannot convert , into a different delimiter as I need to process the string as-is and it can container any character.

Why not split it with =, and make the string after the last ,
the value?
String key = "key1=value1,key2=value2,key3=value3,with,delimeter";
Map<String, String> map = new HashMap<>();
String[] valueKeys = key.split("=");
// {"key", "value,key", "value"}
String lastKey = valueKeys[0];
for(int i = 1; i < valueKeys.length; i++) {
String valueKey = valueKeys[i];
if(i == valueKeys.length - 1) { // It must be the last item in the array
map.put(lastKey, valueKey);
break;
}
int lastComma = valueKey.lastIndexOf(",");
map.put(lastKey, valueKey.substring(0, lastComma));
lastKey = valueKey.substring(lastComma + 1);
}
printMap(map); // Display the map
Result:
key1: value1
key2: value2
key3: value3,with,delimeter
Note: It only works if the key does not contains commas.

Java PatternSyntaxException when replacing characters in a String object

I am trying to create string of this list without the following character , [] as will I want to replace all two spaces after deleting them.
I have tried the following but I am geting the error in the title.
Simple:
[06:15, 06:45, 07:16, 07:46]
Result should look as this:
06:15 06:45 07:16 07:46
Code:
List<String> value = entry.getValue();
String timeEntries = value.toString();
String after = timeEntries.replaceAll(",", " ");
String after2 = after.replaceAll(" ", " ");
String after3 = after2.replaceAll("[", "");
String after4 = after3.replaceAll("]", "");

replaceAll replaces all occurrences that match a given regular expression. Since you just want to match a simple string, you should use replace instead:
List<String> value = entry.getValue();
String timeEntries = value.toString();
String after = timeEntries.replace(",", " ");
String after2 = after.replace(" ", " ");
String after3 = after2.replace("[", "");
String after4 = after3.replace("]", "");

To answer the main question, if you use replaceAll, make sure your 1st argument is a valid regular expression. For your example, you can actually reduce it to 2 calls to replaceAll, as 2 of the substitutions are identical.
List<String> value = entry.getValue();
String timeEntries = value.toString();
String after = timeEntries.replaceAll("[, ]", " ");
String after2 = after.replaceAll("\\[|\\]", "");
But, it looks like you're just trying to concatenate all the elements of a String list together. It's much more efficient to construct this string directly, by iterating your list and using StringBuilder:
StringBuilder builder = new StringBuilder();
for (String timeEntry: entry.getValue()) {
builder.append(timeEntry);
}
String after = builder.toString();

How to extract the value of ID1 and ID2 in a string

I have a string test in which I can see VD1 and and VD2.
How can I extract the value of VD1 and VD2 and store it in string.
String test =
"DomainName=xyz.zzz.com
&ModifiedOn=03%2f17%2f2015
&VD1=MTMwMDE3MDQ%3d
&VD2=B67E48F6969E99A0BC2BEE0E240D2B5C
&SiteLanguage=English"
Here value of VD1=MTMwMDE3MDQ%3d and VD2=B67E48F6969E99A0BC2BEE0E240D2B5C. But these are the dynamic values. Here VD1 and VD2 are seperated by '&'.

Try regex like this :
public static void main(String[] args) throws Exception {
String test = "DomainName=xyz.zzz.com&ModifiedOn=03%2f17%2f2015&VD1=MTMwMDE3MDQ%3d&VD2=B67E48F6969E99A0BC2BEE0E240D2B5C&SiteLanguage=English";
Pattern p = Pattern.compile("VD1=(.*)&VD2=(.*)&");
Matcher m = p.matcher(test);
while(m.find()){
System.out.println(m.group(1));
System.out.println(m.group(2));
}
}
O/P :
MTMwMDE3MDQ%3d
B67E48F6969E99A0BC2BEE0E240D2B5C

You can use regular expressions or use the String index() and split() methods.
A regular expression that matches and captures the VD1 value is
/VD1=([^&]*)/

If you're sure that theres always a "&" behind the values of VD1 and VD2, this kind of splitting will do:
String test = "DomainName=xyz.zzz.com&ModifiedOn=03%2f17%2f2015&VD1=MTMwMDE3MDQ%3d&VD2=B67E48F6969E99A0BC2BEE0E240D2B5C&SiteLanguage=English";
String vd1 = test.substring(test.indexOf("VD1=")+4, test.indexOf("&", test.indexOf("VD1")));
String vd2 = test.substring(test.indexOf("VD2=")+4, test.indexOf("&", test.indexOf("VD2")));
System.out.println("VD1:" + vd1 + "\nVD2:" + vd2);
This is only a demo, for production you'd have to extract the indexes for better performance.

You can use String.split(...) to split a String in pieces. For example, test.split("&") first splits the String in individual tokens (of the form "key=value").
You could do the following to achieve this:
String vd1 = null, vd2 = null;
for (String token : test.split("&")) {
// For each token, we check if it is one of the keys we need:
if (token.startsWith("VD1=")) {
// The number 4 represents the length of the String "vd1="
vd1 = token.substring(4);
} else if (token.startsWith("VD2=") {
vd2 = token.substring(4);
}
}
System.out.println("VD1 = " + vd1);
System.out.println("VD2 = " + vd2);
However, if you want to parse arbitrary keys, consider using a more robust solution (instead of hard-coding the keys in the for-loop).
Also see the documentation for the String class

String test = "DomainName=xyz.zzz.com&Test&ModifiedOn=03%2f17%2f2015&VD1=MTMwMDE3MDQ%3d&VD2=B67E48F6969E99A0BC2BEE0E240D2B5C&SiteLanguage=English";
HashMap<String, String> paramsMap = new HashMap<String, String>();
String[] params = test.split("&");
for (int i=0; i<params.length; i++) {
String[] param = params[i].split("=");
String paramName = URLDecoder.decode(param[0], "UTF-8");
String paramValue = null;
if(param.length > 1)
paramValue = URLDecoder.decode(param[1], "UTF-8");
paramsMap.put(paramName, paramValue);
}
String vd1 = paramsMap.get("VD1");
String vd2 = paramsMap.get("VD2");

How to replace a particular string with value in java

EDIT :
Goal : http://localhost:8080/api/upload/form/test/test
Is it possible to have some thing like `{a-b, A-B..0-9}` kind of pattern and match them and replace with value.
i have following string
http://localhost:8080/api/upload/form/{uploadType}/{uploadName}
there can be any no of strings like {uploadType}/{uploadName}.
how to replace them with some values in java?

[Edited] Apparently you don't know what substitutions you'll be looking for, or don't have a reasonable finite Map of them. In this case:
Pattern SUBST_Patt = Pattern.compile("\\{(\\w+)\\}");
StringBuilder sb = new StringBuilder( template);
Matcher m = SUBST_Patt.matcher( sb);
int index = 0;
while (m.find( index)) {
String subst = m.group( 1);
index = m.start();
//
String replacement = "replacement"; // .. lookup Subst -> Replacement here
sb.replace( index, m.end(), replacement);
index = index + replacement.length();
}
Look, I'm really expecting a +1 now.
[Simpler approach] String.replace() is a 'simple replace' & easy to use for your purposes; if you want regexes you can use String.replaceAll().
For multiple dynamic replacements:
public String substituteStr (String template, Map<String,String> substs) {
String result = template;
for (Map.Entry<String,String> subst : substs.entrySet()) {
String pattern = "{"+subst.getKey()+"}";
result = result.replace( pattern, subst.getValue());
}
return result;
}
That's the quick & easy approach, to start with.

You can use the replace method in the following way:
String s = "http://localhost:8080/api/upload/form/{uploadType}/{uploadName}";
String typevalue = "typeValue";
String nameValue = "nameValue";
s = s.replace("{uploadType}",value).replace("{uploadName}",nameValue);

You can take the string that start from {uploadType} till the end.
Then you can split that string using "split" into string array.
Were the first cell(0) is the type and 1 is the name.

Solution 1 :
String uploadName = "xyz";
String url = "http://localhost:8080/api/upload/form/" + uploadName;
Solution 2:
String uploadName = "xyz";
String url = "http://localhost:8080/api/upload/form/{uploadName}";
url.replace("{uploadName}",uploadName );
Solution 3:
String uploadName = "xyz";
String url = String.format("http://localhost:8080/api/upload/form/ %s ", uploadName);

String s = "http://localhost:8080/api/upload/form/{uploadType}/{uploadName}";
String result = s.replace("uploadType", "UploadedType").replace("uploadName","UploadedName");
EDIT: Try this:
String r = s.substring(0 , s.indexOf("{")) + "replacement";

The UriBuilder does exactly what you need:
UriBuilder.fromPath("http://localhost:8080/api/upload/form/{uploadType}/{uploadName}").build("foo", "bar");
Results in:
http://localhost:8080/api/upload/form/foo/bar

Convert string to array in Java?

I have a string which has the values like this (format is the same):
name:xxx
occupation:yyy
phone:zzz
I want to convert this into an array and get the occupation value using indexes.
Any suggestions?

Basically you would use Java's split() function:
String str = "Name:Glenn Occupation:Code_Monkey";
String[] temp = str.split(" ");
String[] name = temp[0].split(":");
String[] occupation = temp[1].split(":");
The resultant values would be:
name[0] - Name
name[1] - Glenn
occupation[0] - Occupation
occupation[1] - Code_Monkey

Read about Split functnio. You can split your text by " " and then by ":"

I would recommend using String's split function.

Sounds like you want to convert to a property Map rather than an array.
e.g.
String text = "name:xxx occupation:yyy phone:zzz";
Map<String, String> properties = new LinkedHashMap<String, String>();
for(String keyValue: text.trim().split(" +")) {
String[] parts = keyValue.split(":", 2);
properties.put(parts[0], parts[1]);
}
String name = properties.get("name"); // equals xxx
This approach allows your values to be in any order. If a key is missing, the get() will return null.

If you are only interested in the occupation value, you could do:
String s = "name:xxx occupation:yyy phone:zzz";
Pattern pattern = Pattern.compile(".*occupation:(\\S+).*");
Matcher matcher = pattern.matcher(s);
if (matcher.matches()){
String occupation = matcher.group(1);
}

str = "name:xxx occupation:yyy phone:zzz
name:xx1 occupation:yy3 phone:zz3
name:xx2 occupation:yy1 phone:zz2"
name[0] = str.subtsring(str.indexAt("name:")+"name:".length,str.length-str.indexAt("occupation:"))
occupation[0] = str.subtsring(str.indexAt("occupation:"),str.length-str.indexAt("phone:"))
phone[0] = str.subtsring(str.indexAt("phone:"),str.length-str.indexAt("occupation:"))

I got the solution:
String[] temp= objValue.split("\n");
String[] temp1 = temp[1].split(":");
String Value = temp1[1].toString();
System.out.println(value);