Using String to convert to Map structure

Directory String is converted to String to Map limited to special format of personal test cases under Map structure

String conversion to Map architecture

The following is limited to individual tests

Recently, I encountered a problem in my work, that is, I need to put an Map < String, Object > This 1 type is saved, followed by the function of reading. Instead of using the usual serialization method, I remembered that Map. toString () could convert Map to String, but there was no corresponding reverse method.

I want to realize such a function, and I think it is good, so I paste the conversion code as follows, but there are many other ways to serialize map. This is just the reverse conversion of map. toString () implemented by myself:

public Object getValue(String param) {
        Map map = new HashMap();
        String str = "";
        String key = "";
        Object value = "";
        char[] charList = param.toCharArray();
        boolean valueBegin = false;
        for (int i = 0; i < charList.length; i++) {
            char c = charList[i];
            if (c == '{') {
                if (valueBegin == true) {
                    value = getValue(param.substring(i, param.length()));
                    i = param.indexOf('}', i) + 1;
                    map.put(key, value);
                }
            } else if (c == '=') {
                valueBegin = true;
                key = str;
                str = "";
            } else if (c == ',') {
                valueBegin = false;
                value = str;
                str = "";
                map.put(key, value);
            } else if (c == '}') {
                if (str != "") {
                    value = str;
                }
                map.put(key, value);
                return map;
            } else if (c != ' ') {
                str += c;
            }
        }
        return map;
    }

Test case

From simple to complex

public void testFun() {
        String str1 = "{idCard=123, phonenum=1234}";
        String str2 = "{idCard=123, phonenum=1234, map={hhaha=haha}}";
        String str3 = "{idCard=123, phonenum=1234, map={hhaha=haha}, nn={en=ha}}";
        String str4 = "{nn={en=ha}, idCard=123, phonenum=1234, map={hhaha=ni, danshi={ke=shi}}}";
        Map<String, Object> mapresutl1 = (Map<String, Object>) getValue(str1);
        Map<String, Object> mapresutl2 = (Map<String, Object>) getValue(str2);
        Map<String, Object> mapresutl3 = (Map<String, Object>) getValue(str3);
        Map<String, Object> mapresutl4 = (Map<String, Object>) getValue(str4);
        System.out.println(mapresutl1.toString());
        System.out.println(mapresutl2.toString());
        System.out.println(mapresutl3.toString());
        System.out.println(mapresutl4.toString());
    }

Output:

{idCard=123, phonenum=1234} {idCard=123, phonenum=1234, map={hhaha=haha}} {nn={en=ha}, idCard=123, phonenum=1234, map={hhaha=haha}} {nn={en=ha}, idCard=123, phonenum=1234, map={hhaha=ni, danshi={ke=shi}}}

The function is capable of handling Map < String, Object > The string of. toString is flipped to the corresponding Map again, where Object can only be Map type or other basic types. If it is complex, it is not involved here, or the complex structure can be represented by the key-value pair of Map, so it can be used in this way.

Later, we found that there are many ways to serialize, so it is not necessary to implement one by ourselves, and map can also be serialized

The following serialization methods

java comes with, json, hession

There are also Ali's fastjson, protobuff and so on

All of the above can realize the serialization of map

Special format of String to Map

String a ="{se=2016, format=xml, at=en co=3}";

a =  a.substring(1, a.length()-1);
Map docType = new HashMap();  
java.util.StringTokenizer items;  
for(StringTokenizer entrys = new StringTokenizer(a, ", ");entrys.hasMoreTokens();   
docType.put(items.nextToken(), items.hasMoreTokens() ? ((Object) (items.nextToken())) : null)){  
     items = new StringTokenizer(entrys.nextToken(), "=");  
   }

System.out.println(docType);
System.out.println("a:"+docType.get("a"));

It is not necessary to use JSONArray or JSONObject as the transfer intermediary for processing, and String is directly transferred to Map