java正则表达式获取json字符串中指定key的value
<仅支持取JSON字符串中, 简单属性值的配置, 即值内容中不包含[]或{}格式的数据>
import org.apache.commons.lang3.StringEscapeUtils;
import org.apache.commons.lang3.StringUtils;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class JsonAttributeFormatTest {
public static void main(String[] args) {
String parem = "{\"param\":{\"song_id\":\"10023423001\"},\"param2\":{\"song_id\":\"10023423001\",\"sec_code\":\"000001\",\"sec_short_name\":\"万科A\"},\"param3\":{\"song_id\":\"10023423001\",\"sec_code\":\"000001\",\"sec_short_name\":\"万科A\",\"arrtibutes\":{\"id\":2955,\"path\":\"/file/word\",\"fileType\":\"xml\"}},\"param4\":{\"song_id\":\"10023423001\",\"sec_code\":\"000001\",\"sec_short_name\":\"万科A\",\"arrtibutes\":{\"id\":2955,\"path\":\"/file/word\",\"fileType\":\"xml\",\"arrtibutes2\":{\"id\":2955,\"path\":\"/file/word\",\"fileType\":\"xml\"}}},\"param5\":{\"song_id\":\"10023423001\",\"sec_code\":\"000001\",\"arrtibutes\":{\"id\":2955,\"path\":\"/file/word\",\"fileType\":\"xml\"},\"sec_short_name\":\"万科A\"},\"paramList\":[\"name\",\"work\",\"good\"],\"paramList2\":[2,4,6,7],\"paramList3\":[{\"song_id\":\"10023423001\"}],\"paramList4\":[{\"song_id\":\"10023423001\"},{\"song_id\":\"10023423001\",\"sec_code\":\"000001\",\"sec_short_name\":\"万科A\"}],\"parameter\":{\"biz_code\":\"10023423001\",\"biz_title\":\"是东风风光\",\"userList\":[{\"name\":\"张三\",\"phone\":12355566},{\"name\":\"李四\",\"phone\":1567889}]},\"address\":null,\"type\":\"\",\"song_id\":\"132430001\"}";
parem = StringEscapeUtils.unescapeJava(parem);
System.out.println(getFieldListFromJsonStr(parem,"id"));
}
public static List<String> getFieldListFromJsonStr(String jsonStr, String fieldName) {
List<String> fieldValues = new ArrayList<>();
String regex = "(?<=(\"" + fieldName + "\":)).*?(?=(,|\\}))"; //单属性配置,且内容中不包含[]或{}格式数据
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(jsonStr);
while (matcher.find()) {
if (StringUtils.isNotEmpty(matcher.group().trim())) {
fieldValues.add(matcher.group().trim());
}
}
return fieldValues;
}
}
<在JSON字符串中,通过指定属性名称, 获取任意格式的数据>
import org.apache.commons.lang3.StringEscapeUtils;
import org.springframework.util.StringUtils;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.Map;
/**
* jlZhang.oth
*/
public class JsonHandler {
public static void main(String[] args) {
String str = "{\"param\":{\"song_id\":\"10023423001\"},\"param2\":{\"song_id\":\"10023423006\",\"sec_code\":\"000001\",\"sec_short_name\":\"万科A\"},\"param3\":{\"song_id\":\"10023423001\",\"sec_code\":\"000001\",\"sec_short_name\":\"万科A\",\"arrtibutes\":{\"id\":2955,\"path\":\"/file/word\",\"fileType\":\"xml\"}},\"paramList\":[\"name\",\"work\",\"good\"],\"paramList2\":[2,4,6,7],\"paramList3\":[{\"song_id\":\"10023423001\"}],\"paramList4\":[{\"song_id\":\"10023423001\"},{\"song_id\":\"10023423001\",\"sec_code\":\"000001\",\"sec_short_name\":\"万科A\"}],\"parameter\":{\"biz_code\":\"10023423001\",\"biz_title\":\"是东风风光\",\"userList\":[{\"name\":\"张三\",\"phone\":12355566},{\"name\":\"李四\",\"phone\":1567889}]},\"address\":null,\"type\":\"\",\"song_iddd\":true}";
String result = getFiledValueFromJsonStr(str, "arrtibutes", 300);
System.out.println(result);
}
private static String getFiledValueFromJsonStr(String jsonStr, String fieldName, Integer orderFindNumber) {
if (StringUtils.isEmpty(jsonStr) || StringUtils.isEmpty(fieldName)) {
return "";
}
orderFindNumber = (orderFindNumber == null || orderFindNumber <= 1) ? 1 : orderFindNumber;
jsonStr = StringEscapeUtils.unescapeJava(jsonStr);
char[] jsonChar = jsonStr.toCharArray();
// 封装[]以及{}的定位信息
Map<Integer, Integer> mapIndex = new HashMap<Integer, Integer>(); // 记录成对{}的索引
Map<Integer, Integer> listIndex = new HashMap<Integer, Integer>(); // 记录成对[]的索引
Boolean strFlag = null;
LinkedList<Integer> mapMark = new LinkedList<>();
LinkedList<Integer> listMark = new LinkedList<>();
for (int i = 0; i < jsonChar.length; i++) {
char c = jsonChar[i];
if (c == ' ') {
continue;
} else if (c == '"') {
if (strFlag != null && strFlag == true) {
strFlag = null;
} else {
strFlag = true;
}
}
if (strFlag == null) {
if (c == '{') {
mapMark.add(i);
} else if (c == '}') {
mapIndex.put(mapMark.getLast(), i);
mapMark.removeLast();
} else if (c == '[') {
listMark.add(i);
} else if (c == ']') {
listIndex.put(listMark.getLast(), i);
listMark.removeLast();
}
}
}
// 定位该属性名称的索引位置
StringBuilder attrSb = new StringBuilder();
attrSb.append("\"").append(fieldName).append("\"");
int nameLocation = 0;
for (int i = 0; i < orderFindNumber; i++) {
if (nameLocation == 0) {
if (jsonStr.indexOf(attrSb.toString()) == -1) return ""; // 首个属性名没设置直接返回
nameLocation = jsonStr.indexOf(attrSb.toString());
} else {
if (jsonStr.indexOf(attrSb.toString(), nameLocation + 1) == -1) continue; // 后续没找到取上一个属性名
nameLocation = jsonStr.indexOf(attrSb.toString(), nameLocation + 1);
}
}
int markLocation = jsonStr.indexOf(":", nameLocation);
LinkedList<Integer> strIndex = new LinkedList<>();
LinkedList<Integer> cutOut = new LinkedList<>();
for (int i = markLocation + 1; i < jsonChar.length; i++) {
char c = jsonChar[i];
if (c == ' ') {
continue;
} else if (c == '"') {
if (strIndex.size() == 0) {
strIndex.add(i);
} else {
strIndex.add(i + 1);
cutOut.addAll(strIndex);
break;
}
}
if (strIndex.size() == 0) {
if ("n".equalsIgnoreCase(String.valueOf(c)) || "f".equalsIgnoreCase(String.valueOf(c)) || "t".equalsIgnoreCase(String.valueOf(c))) {
// null, false, true值
cutOut.add(i);
int last = (jsonStr.indexOf(":", i) == -1) ? jsonStr.length() - 1 : jsonStr.indexOf(",", i);
// 排除格式: ..."cache":null}],
while (jsonChar[last] == '}' || jsonChar[last] == ']' || jsonChar[last] == ',') {
last = last - 1;
}
cutOut.add(last + 1);
break;
}
if (Character.isDigit(c)) {
cutOut.add(i);
int last = (jsonStr.indexOf(":", i) == -1) ? jsonStr.length() - 1 : jsonStr.indexOf(",", i);
// 排除格式: ..."cache":456}],
while (jsonChar[last] == '}' || jsonChar[last] == ']' || jsonChar[last] == ',') {
last = last - 1;
}
cutOut.add(last + 1);
break;
}
if (c == '{') {
Integer last = mapIndex.get(i);
if (null != last) {
cutOut.add(i);
cutOut.add(last + 1);
}
break;
} else if (c == '[') {
Integer last = listIndex.get(i);
if (null != last) {
cutOut.add(i);
cutOut.add(last + 1);
}
break;
}
}
}
// 获取最终的结果
if (cutOut.size() == 0) return "";
String result = jsonStr.substring(cutOut.getFirst(), cutOut.getLast());
return result;
}
}