java - How to escape slashes in Gson -

according json specs, escaping "/" optional.

gson not default, dealing webservice expecting escaped "/". want send "somestring\\/someotherstring". ideas on how achieve this?

to make things clearer: if try deserialize "\\/" gson, send "\\\\/", not want!

answer: custom serializer

you can write own custom serializer - have created 1 follows rule want / \\/ if string escaped want stay \\/ , not \\\\/.

package com.dominikangerer.q29396608;  import java.lang.reflect.type;  import com.google.gson.jsonelement; import com.google.gson.jsonprimitive; import com.google.gson.jsonserializationcontext; import com.google.gson.jsonserializer;  public class escapestringserializer implements jsonserializer<string> {      @override     public jsonelement serialize(string src, type typeofsrc,             jsonserializationcontext context) {         src = createescapedstring(src);         return new jsonprimitive(src);     }      private string createescapedstring(string src) {         // stringbuilder new string         stringbuilder builder = new stringbuilder();          // first occurrence         int index = src.indexof('/');         // lastadded starting @ position 0         int lastadded = 0;          while (index >= 0) {             // append first part without /             builder.append(src.substring(lastadded, index));              // if / doesn't have \ directly in front - add \             if (index - 1 >= 0 && !src.substring(index - 1, index).equals("\\")) {                 builder.append("\\");                 // if @ index 0 add because - it's                 // first character             } else if (index == 0) {                 builder.append("\\");             }              // change last added index             lastadded = index;             // change index new occurrence of /             index = src.indexof('/', index + 1);         }          // add rest of string         builder.append(src.substring(lastadded, src.length()));         // return new string         return builder.tostring();     } } 

this create following string:

"12 /first /second \\/third\\/fourth\\//fifth"` 

the output:

"12 \\/first \\/second \\/third\\/fourth\\/\\/fifth" 

register custom serializer

than of course need pass serializer gson on setup this:

gson gson = new gsonbuilder().registertypeadapter(string.class, new escapestringserializer()).create(); string json = gson.tojson(yourobject); 

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downloadable & executable example

you can find answer , exact example in github stackoverflow answers repo:

gson customserializer escape string in special way dominikangerer

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see also

• gson user guide - custom serializers , deserializers