Java遍历json字符串取值的实例
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2024-01-27 13:25:40
java遍历json字符串，取得相应kv值时，各种麻烦，比如将json中的list取出来转为jsonarray，再将list中的object转化为map，再取值（之前的做法...
java遍历json字符串，取得相应kv值时，各种麻烦，比如将json中的list取出来转为jsonarray，再将list中的object转化为map，再取值（之前的做法），仙子啊通过阿里的fastjson，可以很方便的直接将str转化为jsonarray，再将里面的object强转为jsonobject，然后再通过obj.getinteger(“key”)和obj.getstring(“key”)等取值。
jsonarray json = (jsonarray) jsonarray.parse(str);
for (object obj : json) {
jsonobject jo = (jsonobject)obj;
int status = jo.getinteger("status");
string message= jo.getstring("message");
system.out.println("status---" + status + "---message---" + message);
}
1.当json字符串中有数组和map对象，遍历数据，数据格式如下：
[
{
"status":0,
"tags":[
"check:ntp"
],
"timestamp":1492151922.198,
"check":"datadog.agent.check_status",
"host_name":"song-2",
"message":null,
"id":2
},
{
"status":0,
"tags":null,
"timestamp":1492151922.2325,
"check":"datadog.agent.up",
"host_name":"song-2",
"message":null,
"id":5
}
]
解析上面json字符串数据，如果不使用如fastjson或者gson时，解析方法如下：
方法一
/**
* 主机详情中，异常错误信息的报错的平台服务状态和message
* @param str
* @return
* @throws exception
*/
private list<map<string,string>> operstr(string str) throws exception{
list<map<string,string>> mlist = new arraylist<map<string,string>>();//探针开启的服务名list
jsonarray json = (jsonarray) jsonarray.parse(str);
map<string,object> objmap = null;
map<string,string> resmap = null;
for (object obj : json) {
objmap = obj2map(obj);
@suppresswarnings("unchecked")
map<string,object> mobj = (map<string, object>) objmap.get("map");
int status = (integer) mobj.get("status");
if(status != 0){
resmap = new hashmap<string,string>();
switch (status) {
case 1:
resmap.put("status","warning");
break;
case 2:
resmap.put("status","error");
break;
case 3:
resmap.put("status","crit");
break;
default:
break;
}
resmap.put("servicename", ((string) mobj.get("check")).split("\\.")[0]);
resmap.put("msg", (string)mobj.get("message"));
mlist.add(resmap);
}
}
return mlist;
}
/**
* object转map
* @param obj
* @return
* @throws exception
*/
public map<string,object> obj2map(object obj) throws exception{
if(obj == null){
return null;
}
map<string,object> map=new hashmap<string, object>();
field[] fields = obj.getclass().getdeclaredfields();
for(field field:fields){
field.setaccessible(true);
map.put(field.getname(), field.get(obj));
}
return map;
}
方法二
/**
* 主机详情中，异常错误信息的报错的平台服务状态和message
* @param str
* @return
* @throws exception
*/
private list<map<string,string>> operstr(string str) throws exception{
list<map<string,string>> mlist = new arraylist<map<string,string>>();//探针开启的服务名list
jsonarray json = (jsonarray) jsonarray.parse(str);
map<string,string> resmap = null;
for (object obj : json) {
jsonobject jo = (jsonobject)obj;
int status = jo.getinteger("status");
if(status != 0){
resmap = new hashmap<string,string>();
switch (status) {
case 1:
resmap.put("status","warning");
break;
case 2:
resmap.put("status","error");
break;
case 3:
resmap.put("status","crit");
break;
default:
break;
}
resmap.put("servicename", (jo.getstring("check")).split("\\.")[0]);
resmap.put("msg", jo.getstring("message"));
mlist.add(resmap);
}
}
return mlist;
}
2.当json字符串中是数组包含数组时候，遍历数据，数据格式如下：
[
[
"haproxy",
"haproxy",
0,
"error",
"swdfghyjuikl",
{
}
],
[
"gearmand",
"gearmand",
0,
"error",
"'found no valid connections in list: [<gearmanconnection localhost:4730 connected=false>]'",
{
"version":"[8, 4, 20]"
}
]
]
方法一
/**
* 通过查询agentchecksstr解析得到异常信息
* @param agentchecksstr
* @return
*/
private list<map<string,string>> getexceptinfofromagentchecks(string agentchecksstr){
list<map<string,string>> mlist = new arraylist<map<string,string>>();//探针开启的服务名list
//mlist 主机详情中，异常错误信息的报错的平台服务状态和message
object jsonarray = jsonarray.parse(agentchecksstr);
@suppresswarnings("unchecked")
list<list<object>> list= (list<list<object>>) jsonarray;
map<string,string> map = null;
for(int i=0;i<list.size();i++){
map = new hashmap<string,string>();
string status = list.get(i).get(3).tostring();
if(!status.equals("ok")){
string servicename = list.get(i).get(0).tostring();
string msg = list.get(i).get(4).tostring();
map.put("servicename", servicename);
map.put("status", status);
map.put("msg", msg);
mlist.add(map);
}
}
return mlist;
}
方法二
/**
* 通过查询agentchecksstr解析得到异常信息
* @param agentchecksstr
* @return
*/
private list<map<string,string>> getexceptinfofromagentchecks(string agentchecksstr){
//探针开启的服务名list
list<map<string,string>> mlist = new arraylist<map<string,string>>();
jsonarray jsonarray = (jsonarray) jsonarray.parse(agentchecksstr);
map<string,string> map = null;
for (object obj : jsonarray) {
map = new hashmap<string,string>();
jsonarray ja = (jsonarray)obj;
string status = ja.getstring(3);
if(!status.equals("ok")){
string servicename = ja.getstring(0);
string msg = ja.getstring(4);
map.put("servicename", servicename);
map.put("status", status);
map.put("msg", msg);
mlist.add(map);
}
}
return mlist;
}
gson将json字符串转化为json对象：
import com.google.gson.gson;
import com.google.gson.jsonarray;
import com.google.gson.jsonelement;
import com.google.gson.jsonobject;
import com.google.gson.jsonparser;
public class maintest {
public static void main(string[] args) throws exception{
string jsonstr0 = "{\"alarmdetails\":{\"conditiondetails\":{\"alarmid\":7,\"alarmnodatanotifytime\":1,\"alarmnowserieswaittime\":2},\"conditionstatic\":{\"alarmid\":7,\"conditionaggregate\":\"avg\",\"conditionoperator\":1,\"conditionthresholdtime\":5,\"conditionthresholdvalue\":\"123\"},\"metricdetails\":{\"alarmid\":7,\"metricaggregater\":\"avg\",\"metricby\":\"host\",\"metricexcludetag\":\"host:paas-177\",\"metricname\":\"system.cpu.user\",\"metricq\":\"avg:system.cpu.user{#address:wuhan,!host:paas-177}by{host}\",\"metrictag\":\"#address:wuhan\"},\"notify\":[{\"alarmid\":7,\"notifychannel\":5,\"notifyuserid\":1},{\"alarmid\":7,\"notifychannel\":5,\"notifyuserid\":2}],\"view\":{\"alarmexpression\":\"avg(last_5m)avg:system.cpu.user{#address:wuhan,!host:paas-177}by{host}>123.0\",\"alarmid\":7,\"alarmlastvalue\":\"up\",\"alarmname\":\"static_metric\",\"alarmstatus\":1,\"alarmtype\":2,\"alarmtypejoin\":3,\"createtime\":\"2017-06-28 17:25:52.0\",\"createuserid\":1,\"isdisable\":false,\"lastalarmtime\":\"2017-06-28 17:25:27.0\",\"metricname\":\"system.cpu.user\",\"metrictag\":\"#address:wuhan\",\"updatetime\":\"2017-06-29 15:49:18.0\"}},\"alarmid\":7,\"allmark\":{\"avg:system.cpu.user{host:cfeng-4,#address:wuhan,!host:paas-177}\":{\"changeputtime\":true,\"lastputtsdbtime\":1499655343,\"lastsuccesschecktime\":1499655349,\"series\":\"avg:system.cpu.user{host:cfeng-4,#address:wuhan,!host:paas-177}\",\"tagmap\":{\"host\":\"cfeng-4\",\"#address\":\"wuhan\",\"!host\":\"paas-177\"}}},\"jointype\":3,\"usemetricunit\":\"percent\",\"validatadetails\":{\"status\":0,\"validatamerges\":[{\"alarmmarkdto\":{\"changeputtime\":true,\"lastputtsdbtime\":1499655343,\"lastsuccesschecktime\":1499655349,\"series\":\"avg:system.cpu.user{host:cfeng-4,#address:wuhan,!host:paas-177}\",\"tagmap\":{\"host\":\"cfeng-4\",\"#address\":\"wuhan\",\"!host\":\"paas-177\"}},\"status\":0,\"tag\":\"host:cfeng-4\",\"validatanodata\":{\"currenttime\":1499655349,\"isnodata\":false,\"lastsuccesschecktime\":1499655349,\"series\":\"avg:system.cpu.user{host:cfeng-4,#address:wuhan,!host:paas-177}\",\"tag\":{\"host\":\"cfeng-4\",\"#address\":\"wuhan\",\"!host\":\"paas-177\"},\"thresholdtime\":60},\"validatastatic\":{\"convertothresholdvalue\":123.0,\"end\":1499655343,\"intervalaggregator\":\"avg\",\"isalart\":true,\"operator\":1,\"series\":\"avg:system.cpu.user{host:cfeng-4,#address:wuhan,!host:paas-177}\",\"start\":1499655043,\"sysunit\":\"percent\",\"tag\":{\"#address\":\"wuhan\",\"host\":\"cfeng-4\",\"!host\":\"paas-177\"},\"thresholdtime\":300,\"thresholdvalue\":\"123\",\"value\":5.715769243240357}}],\"validatatimeseconds\":1499655349}}";
string jsonstr1 = "{\"alarmdetails\":{\"conditiondetails\":{\"alarmid\":7,\"alarmnodatanotifytime\":1,\"alarmnowserieswaittime\":2},\"conditionstatic\":{\"alarmid\":7,\"conditionaggregate\":\"avg\",\"conditionoperator\":1,\"conditionthresholdtime\":5,\"conditionthresholdvalue\":\"123\"},\"metricdetails\":{\"alarmid\":7,\"metricaggregater\":\"avg\",\"metricby\":\"host\",\"metricexcludetag\":\"host:paas-177\",\"metricname\":\"system.cpu.user\",\"metricq\":\"avg:system.cpu.user{#address:wuhan,!host:paas-177}by{host}\",\"metrictag\":\"#address:wuhan\"},\"notify\":[{\"alarmid\":7,\"notifychannel\":5,\"notifyuserid\":1},{\"alarmid\":7,\"notifychannel\":5,\"notifyuserid\":2}],\"view\":{\"alarmexpression\":\"avg(last_5m)avg:system.cpu.user{#address:wuhan,!host:paas-177}by{host}>123.0\",\"alarmid\":7,\"alarmlastvalue\":\"up\",\"alarmname\":\"static_metric\",\"alarmstatus\":1,\"alarmtype\":2,\"alarmtypejoin\":3,\"createtime\":\"2017-06-28 17:25:52.0\",\"createuserid\":1,\"isdisable\":false,\"lastalarmtime\":\"2017-06-28 17:25:27.0\",\"metricname\":\"system.cpu.user\",\"metrictag\":\"#address:wuhan\",\"updatetime\":\"2017-06-29 15:49:18.0\"}},\"alarmid\":7,\"allmark\":{\"avg:system.cpu.user{host:cfeng-4,#address:wuhan,!host:paas-177}\":{\"changeputtime\":true,\"lastputtsdbtime\":1499655374,\"lastsuccesschecktime\":1499655379,\"series\":\"avg:system.cpu.user{host:cfeng-4,#address:wuhan,!host:paas-177}\",\"tagmap\":{\"host\":\"cfeng-4\",\"#address\":\"wuhan\",\"!host\":\"paas-177\"}}},\"jointype\":3,\"usemetricunit\":\"percent\",\"validatadetails\":{\"status\":0,\"validatamerges\":[{\"alarmmarkdto\":{\"changeputtime\":true,\"lastputtsdbtime\":1499655374,\"lastsuccesschecktime\":1499655379,\"series\":\"avg:system.cpu.user{host:cfeng-4,#address:wuhan,!host:paas-177}\",\"tagmap\":{\"host\":\"cfeng-4\",\"#address\":\"wuhan\",\"!host\":\"paas-177\"}},\"status\":0,\"tag\":\"host:cfeng-4\",\"validatanodata\":{\"currenttime\":1499655379,\"isnodata\":false,\"lastsuccesschecktime\":1499655379,\"series\":\"avg:system.cpu.user{host:cfeng-4,#address:wuhan,!host:paas-177}\",\"tag\":{\"host\":\"cfeng-4\",\"#address\":\"wuhan\",\"!host\":\"paas-177\"},\"thresholdtime\":60},\"validatastatic\":{\"convertothresholdvalue\":123.0,\"end\":1499655374,\"intervalaggregator\":\"avg\",\"isalart\":true,\"operator\":1,\"series\":\"avg:system.cpu.user{host:cfeng-4,#address:wuhan,!host:paas-177}\",\"start\":1499655074,\"sysunit\":\"percent\",\"tag\":{\"#address\":\"wuhan\",\"host\":\"cfeng-4\",\"!host\":\"paas-177\"},\"thresholdtime\":300,\"thresholdvalue\":\"123\",\"value\":5.089640821729388}}],\"validatatimeseconds\":1499655379}}";
set<string> set = new hashset<string>();
set.add(jsonstr0);
set.add(jsonstr1);
gson gs = new gson();
list<object> eventlist = new arraylist<object>();
for (string str : set) {
jsonobject returndata = new jsonparser().parse(str).getasjsonobject();
jsonobject ad = returndata.get("alarmdetails").getasjsonobject();
jsonobject vd = returndata.get("validatadetails").getasjsonobject();
jsonarray vm = vd.get("validatamerges").getasjsonarray();
jsonarray nf = ad.get("notify").getasjsonarray();
jsonobject v = ad.get("view").getasjsonobject();
string validatatimeseconds = vd.get("validatatimeseconds").tostring();
for (jsonelement je : vm) {
je.getasjsonobject().add("view", v);
je.getasjsonobject().add("notify", nf);
je.getasjsonobject().addproperty("validatatimeseconds", long.parselong(validatatimeseconds));
eventlist.add(je);
}
}
for (object obj : eventlist) {
string inparam = gs.tojson(obj);
system.out.println(inparam);
}
system.out.println(gs.tojson(eventlist));
}
}
//获取设备信息（只有硬件设备和虚拟设备有）
hashmap<string,string> parammap = new hashmap<string,string>();
parammap.put("hostid", mhostid);
parammap.put("ptype", dto.getptype());
parammap.put("type_flag", dto.gettypeflag());
parammap.put("api_key", apikey);
string resstr = httputils.get(device_info_url, parammap);
jsonobject jobj = json.parseobject(resstr);
jsonobject obj = (jsonobject)jobj.get("result");
if(obj.size() != 0){
string restr = jobj.get("result").tostring();
deviceinfodto deviceinfodto = new gson().fromjson(restr, deviceinfodto.class);
dto.setdeviceinfo(deviceinfodto);
}
list<map<integer, long>> result = new arraylist<map<integer, long>>();
map<string, string> timemap = null;
list<map<string, string>> timearr = new arraylist<map<string, string>>();
for (int j = 0; j < result.size(); j++) {
timemap = new hashmap<string, string>();
if (j == result.size() - 1) {
timemap.put("starttime",result.get(j).get(result.get(j).keyset().iterator().next()) + "");
timemap.put("endtime", system.currenttimemillis() + "");
} else {
timemap.put("starttime", result.get(j).get(result.get(j).keyset().iterator().next()) + "");
timemap.put("endtime", (result.get(j+1).get(result.get(j+1).keyset().iterator().next()) - 1) + "");
}
timemap.put("hostname", "*");
//1:info,2:error,3:success,4:warning
integer key = result.get(j).keyset().iterator().next();
if (key == 1) {
timemap.put("status", "info");
} else if (key == 2) {
timemap.put("status", "error");
} else if (key == 3) {
timemap.put("status", "success");
} else if (key == 4) {
timemap.put("status", "warning");
}
timearr.add(timemap);
}
以上这篇java遍历json字符串取值的实例就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持。
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