Develop Reference

How to convert utf8 string to escape string in JSON Java?

I want to convert a UTF-8 string to escape \uXXX format in value of JSON Object.
I used both JSON Object and Gson, but did not work for me in this case:
JSONObject js = new JSONObject();
js.put("lastReason","nguyễn");
System.out.println(js.toString());
and
Gson gson = new Gson();
String new_js = gson.toJson(js.toString());
System.out.println(new_js);
Output: {"test":"nguyễn"}
But i am expect that my result is:
Expected Output: {"test":"nguy\u1EC5n"}
Any solutions for this case, please help me to resolve it.

You can use apache commons-text library to change a string to use Unicode escape sequences. Use org.apache.commons.text.StringEscapeUtils to translate the text before adding it to JSONObject.
StringEscapeUtils.escapeJava("nguyễn")
will produce
nguy\u1EC5n
One possible problem with using StringEscapeUtils might be that it will escape control characters as well. If there is a tab character at the end of the string it will be translated to \t. I.e.:
StringEscapeUtils.escapeJava("nguyễn\t")
will produce an incorrect string:
nguy\u1EC5n\t
You can use org.apache.commons.text.translate.UnicodeEscaper to get around this but it will translate every character in the string to a Unicode escape sequence. I.e.:
UnicodeEscaper ue = new UnicodeEscaper();
ue.translate(rawString);
will produce
\u006E\u0067\u0075\u0079\u1EC5\u006E
or
\u006E\u0067\u0075\u0079\u1EC5\u006E\u0009
Whether it is a problem or not is up to you to decide.

Gson adding backslash in String

I am having user defined object Customer which has multiple attributes ,in one of the attributes we can have single , double quotes and backslash as well. While converting the object to string Gson library is adding backslash in it.
I am using below code to achive this but it is not working.
Gson gson = new GsonBuilder().disableHtmlEscaping().create();
JsonElement jsonString = gson.toJsonTree(triggerModel);
Output is
{
"customerId": "1234",
"customerName": "Loren",
"customerAddress": [
{
"postalcode": "67676",
"lane": "\"LA16767",
"houseNumber": "2025",
"society": "null"
}
]
}
In lane attribute the original value was "LA16767 but it is adding one backslash character. How to write this in such a way string with single ,double quotes and backslash are handled using same line of code.

Output provided by Gson is correct because "lane": ""LA16767" would not have been a valid json.
From json docs
A string is a sequence of zero or more Unicode characters, wrapped in double quotes, using backslash escapes. A character is represented as a single character string. A string is very much like a C or Java string.
You had mentioned :
How to write this in such a way string with single ,double quotes and backslash are handled using same line of code.
You need not do anything special to handle single ,double quotes and backslash characters. Gson will automatically escape them for you.
Any app (server, UI, etc,) who is consuming your json, will correctly parse "\"LA16767" as "LA16767 going by the json conventions.

How to escape or remove "\" from the gson generated string?

I am loading a value from the property file and then passing it to gson method for converting it to final json object. However, the value coming from the property file has double quotes for which the gson is adding "\" to the output. I have scanned down the whole web but unable to find a solution
The property file contains
0110= This is a test for the renewal and the "Renewal no:"
Here's my code
public String toJSONString(Object object) {
GsonBuilder gsonBuilder = new GsonBuilder();
Gson gson = gsonBuilder.create();
//Note object here is the value from the property file
return gson.toJson(object);
}
This produces
"{ResponseCode:0110,ResponseText:This is a test for the renewal and the \"Renewal no:\"}"
I am not sure in the output, why it is adding or wrapping the \ around the literals or where ever we have the double quotes in the property file value?

Based on comments on your question, the object parameter is actually referencing a Java String with the value
{ResponseCode:0110,ResponseText:This is a test for the renewal and the "Renewal no:"}
I can't say why, but that's what your String contains.
String is a special type which Gson interprets as a JSON string. Since " is a special character that must be escaped in JSON strings, that's what Gson does and produces the JSON string.
"{ResponseCode:0110,ResponseText:This is a test for the renewal and the \"Renewal no:\"}"

The \ character is escaping special characters like " in the string. You can't store a " in a string without a leading . It has to be \".
You remove the slashes when you display any output string.
Apache Commons has a library for handling escaping and unescaping strings: https://commons.apache.org/proper/commons-lang/javadocs/api-2.6/org/apache/commons/lang/StringEscapeUtils.html

How can I replace JSON element in JSON object with another string in java?

JSON object :
{
"test1":"2",
"test2":"4",
"test3":"5"
}
I need to replace "test2":"4" with "test2":"this is test".
How can I do this with Java?

If you want to replace string "test2":"4" with "this is test" then it will make your json unparsable and if you want to change the content to the key "test2" from "4" to "this is test" then you can use JSON parser apis like gson or jackson etc.

I need to replace "test2":"4" by "this is test" string.
How can I do this with java?.
Using String API, for example with String::replace, remembering:
Strings in Java are immutable
You need to scape special characters
String result = yourJsonString.replace("\"test2\":\"4\"", "\"test2\":\"this is test\"");

Store Backward slash and forward slash in java string

I am parsing below string value into OData query through java code.
objects.put("EndDate", "\/Date(1441756800)\/";
How can i parse the /Date(1441756800)/ into a string in java.
I have tried with below :
objects.put("EndDate", ""\\""//"Date(1441756800)""\\""//"";
throws error:(

I never used OData so I may not understand your question correctly, but if you are asking how to write \/Date(1441756800)\/ as String then you need to escape \ as it is String special character (used for instance when escaping or when creating other special characters like line separators \n).
So try with "\\/Date(1441756800)\\/"

Try this - objects.put("EndDate", "'Date(1441756800)'";