1 public String makeReadable(String json) {
 2    StringBuilder sb = new StringBuilder();
 3    int indent = 0;
 4    boolean inString = false;
 5    char lastChar = ' ';
 6    char c;
 7    for (int i = 0; i < json.length(); i++) {
 8       // Schleife für jedes Zeichen
 9       c = json.charAt(i);
10       if (c == '"' && lastChar != '\\\\') {
11          inString = !inString;
12       }
13       if (inString) {
14          // innerhalb Strings darf nichts geändert werden!
15          sb.append(c);
16       } else {
17          // normales Verhalten außerhalb eines Strings
18          switch (c) {
19          case '\\n':
20          case ' ':
21          case '\\t':
22             // alte Formatierungen entfernen
23             break;
24          case '[':
25             sb.append("\\n");
26             appendIndents(sb, indent);
27             sb.append(c);
28             sb.append("\\n");
29             appendIndents(sb, ++indent);
30             break;
31          case '{':
32             sb.append(c);
33             sb.append("\\n");
34             appendIndents(sb, ++indent);
35             break;
36          case '}':
37          case ']':
38             sb.append("\\n");
39             appendIndents(sb, --indent);
40             sb.append(c);
41             break;
42          case ':':
43             sb.append(' ');
44             sb.append(c);
45             sb.append(' ');
46             break;
47          case ',':
48             sb.append(c);
49             sb.append('\\n');
50             appendIndents(sb, indent);
51             break;
52          default:
53             sb.append(c);
54          }
55       }
56       lastChar = c;
57    }
58    return sb.toString();
59 }
60 
61 private void appendIndents(StringBuilder sb, int indent) {
62    for (int i = 0; i < indent; i++) {
63       sb.append("\\t");
64    }
65 
66 }