io.micrometer.core.instrument.util.JsonUtils Maven / Gradle / Ivy
/**
* Copyright 2018 VMware, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.micrometer.core.instrument.util;
public final class JsonUtils {
private JsonUtils() {
}
/**
* Based on https://stackoverflow.com/a/49564514/510017
*
* @param unformattedJsonString JSON string that has not been formatted at all.
* @return A best-effort at pretty printed JSON, even for malformed JSON.
*/
public static String prettyPrint(String unformattedJsonString) {
StringBuilder sb = new StringBuilder();
int indentLevel = 0;
boolean inQuote = false;
for (char charFromUnformattedJson : unformattedJsonString.toCharArray()) {
switch (charFromUnformattedJson) {
case '"':
// switch the quoting status
inQuote = !inQuote;
sb.append(charFromUnformattedJson);
break;
case ' ':
// For space: ignore the space if it is not being quoted.
if (inQuote) {
sb.append(charFromUnformattedJson);
}
break;
case '{':
case '[':
// Starting a new block: increase the indent level
sb.append(charFromUnformattedJson);
indentLevel++;
appendIndentedNewLine(indentLevel, sb);
break;
case '}':
case ']':
// Ending a new block; decrese the indent level
indentLevel--;
appendIndentedNewLine(indentLevel, sb);
sb.append(charFromUnformattedJson);
break;
case ',':
// Ending a json item; create a new line after
sb.append(charFromUnformattedJson);
if (!inQuote) {
appendIndentedNewLine(indentLevel, sb);
}
break;
default:
sb.append(charFromUnformattedJson);
}
}
return sb.toString();
}
/**
* Print a new line with indention at the beginning of the new line.
*
* @param indentLevel
* @param stringBuilder
*/
private static void appendIndentedNewLine(int indentLevel, StringBuilder stringBuilder) {
stringBuilder.append("\n");
for (int i = 0; i < indentLevel; i++) {
// Assuming indention using 2 spaces
stringBuilder.append(" ");
}
}
}