如何在Gson中跳转斜杠

Question

根据json规范，转义“/”是可选的。

Gson默认不会这样做，但我正在处理一个期待转义的web服务“/”。所以我想发送的是“somestring\\/someotherstring”。任何想法如何实现这一目标？

为了让事情更清晰：如果我尝试反序列化“\\/”与GSON，它会发送“\\\\/”，这是不我想要的！

Answer 1

答：自定义序列

您可以编写自己的自定义序列化 - 我已创建了一个下面要/是\\/的规则，但如果字符串的长度已经逃脱你想让它留下来\\/而不是\\\\/。

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 for the new String 
     StringBuilder builder = new StringBuilder(); 

     // First occurrence 
     int index = src.indexOf('/'); 
     // lastAdded starting at position 0 
     int lastAdded = 0; 

     while (index >= 0) { 
      // append first part without a/
      builder.append(src.substring(lastAdded, index)); 

      // if/doesn't have a \ directly in front - add a \ 
      if (index - 1 >= 0 && !src.substring(index - 1, index).equals("\\")) { 
       builder.append("\\"); 
       // if we are at index 0 we also add it because - well it's the 
       // first character 
      } else if (index == 0) { 
       builder.append("\\"); 
      } 

      // change last added to index 
      lastAdded = index; 
      // change index to the new occurrence of the/
      index = src.indexOf('/', index + 1); 
     } 

     // add the rest of the string 
     builder.append(src.substring(lastAdded, src.length())); 
     // return the new String 
     return builder.toString(); 
    } 
} 

这将从以下字符串创建：

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

输出：

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

注册您的自定义序列

当然比你需要通过这串行器到Gson安装像这样：

Gson gson = new GsonBuilder().registerTypeAdapter(String.class, new EscapeStringSerializer()).create(); 
String json = gson.toJson(yourObject); 

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&下载可执行实例

你可以找到这个答案，在我的github计算器答案回购的具体例子：

Gson CustomSerializer to escape a String in a special way by DominikAngerer

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参见

• Gson User Guide - Custom serializers and deserializers