用Java对JSON字符串进行格式化输出

public class JsonFormatUtil {

/**
* 对json字符串格式化输出
* @param jsonStr
* @return
*/
public static String formatJson(String jsonStr) {
if (null == jsonStr || "".equals(jsonStr)) return "";
StringBuilder sb = new StringBuilder();
char last = '\0';
char current = '\0';
int indent = 0;
for (int i = 0; i < jsonStr.length(); i++) {
last = current;
current = jsonStr.charAt(i);
switch (current) {
case '{':
case '[':
sb.append(current);
sb.append('\n');
indent++;
addIndentBlank(sb, indent);
break;
case '}':
case ']':
sb.append('\n');
indent--;
addIndentBlank(sb, indent);
sb.append(current);
break;
case ',':
sb.append(current);
if (last != '\\') {
sb.append('\n');
addIndentBlank(sb, indent);
}
break;
default:
sb.append(current);
}
}

return sb.toString();
}

/**
* 添加space
* @param sb
* @param indent
*/
private static void addIndentBlank(StringBuilder sb, int indent) {
for (int i = 0; i < indent; i++) {
sb.append('\t');
}
}
}