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Java append `HashMap` values to existing HashMap if key matches

I have below HashMap(to.String()) printed below.
HashMap<String, HashMap<String, HashMap<String, Integer>>> abc = new HashMap<>();
HashMap abc = {disabled={account={testConfiguration=1, iterate=1}}}
I want to append {group={iterate=1}} to existing map if key disabled matches.
Finally my map should look like below, how can I achieve it?
HashMap abc = {disabled={account={testConfiguration=1, iterate=1}, {group={iterate=1}}}

I think you want this:
abc.computeIfPresent("disabled", (k,v) -> {
v.put("group", yourValue);
return v;
});
or simply:
if (abc.containsKey("disabled")) {
abc.get("disabled").put("group", yourValue);
}
I personally prefer the first approach, since it's a bit faster and works properly with concurrent maps.

Here is the example for your desired output
disabled={account={testConfiguration=1, iterate=1}, group={iterate=1}}
HashMap<String, Integer> accountmap = new HashMap<>();
HashMap<String, Integer> groupMap = new HashMap<>();
HashMap<String, HashMap<String, Integer>> disableMap = new HashMap<>();
HashMap<String, HashMap<String, HashMap<String, Integer>>> abc = new HashMap<>();
accountmap.put("testConfiguration",1);
accountmap.put("iterate",1);
disableMap.put("account",accountmap);
abc.put("disabled", disableMap);
if(abc.containsKey("disabled")){
groupMap.put("iterate", 1);
disableMap.put("group",groupMap);
}
System.out.println(abc.entrySet());

The below code gives you the hashmap in the following format
{disabled={account={testConfiguration=1, iterate=1}, group={iterate=1}}}
public static void main(String []args) {
HashMap<String, HashMap<String, HashMap<String, Integer>>> abc = new HashMap<>();
// HashMap abc = {disabled={account={testConfiguration=1, iterate=1}}}
HashMap<String, Integer> thirdHash = new HashMap<>();
thirdHash.put("testConfiguration", 1);
thirdHash.put("iterate", 1);
HashMap<String, HashMap<String, Integer>> secondHash = new HashMap<>();
secondHash.put("account", thirdHash);
abc.put("disabled", secondHash);
// append {group={iterate=1}}
HashMap<String, Integer> appendFirst = new HashMap();
appendFirst.put("iterate", 1);
if (abc.containsKey("disabled")) {
abc.get("disabled").put("group", appendFirst);
}
System.out.println(abc);
}
Happy Coding.

Problems building hashmap java

I'm in a little trouble building a hashmap but it took me a lot of time and I don't have a lot of experience with this kind of objects, my problem is when building the next hashmap:
Map<String, Map<String, Map<String, Object>>> map = new HashMap<String, Map<String, Map<String, Object>>>();
Map<String, Map<String, Object>> map1 = new HashMap<String, Map<String, Object>>();
Map<String, Object> map2 = new HashMap<String, Object>();
Map<String, Object> map3 = new HashMap<String, Object>();
map2.put("one",1);
map1.put("two", map2);
map.put("cero", map1);
System.out.println(map);
The output is:
{cero={two={one=1}}}
But now I want to add another key percent with string value 10 at cero key level like:
{percent=10,cero={two={one=1}}}
I tried something like:
Map<String, Object> map3 = new HashMap<String, Object>();
map3.put("percent", "10");
map.get("cero").putAll(map3);
There is an error in putAll method 'cause java needs a Map<String, Map<String, Object>> kind of object but I only need to add that percent property. Hope I'm clear with my question and you guys can help me, thanks.

We can try to add map1 to map3
Map<String, Map<String, Map<String, Object>>> map = new HashMap<String,
Map<String, Map<String, Object>>>();
Map<String, Map<String, Object>> map1 = new HashMap<String, Map<String, Object>>
();
Map<String, Object> map2 = new HashMap<String, Object>();
Map<String, Object> map3 = new HashMap<String, Object>();
map2.put("one",1);
map1.put("two", map2);
map3.put("percent", "10");
map3.put("cero",map1);
System.out.println(map3);
This gives following structure in map3
{percent=10,cero={two={one=1}}}

how do i write this as a list<map<string, string> structure in java

how do i write this as a list structure in java
In this case i want the structure to be like this, Where options is also a key in another
hashmap called styles
options[{"value":"0","label":"zero"},{"value":"1","label":"one"},
{"value":"2","label":"two"}]
Here if i want to access options[1].value should give me 1 and options[2].label should give me two.
How can i achieve this with
LIst<Map<string><string[]>>?
Also Can i pass "options" array as one of the keys in my hash map
protected Map<String, String[]> getValueProperties(int view, Field field) {
Map<String, String> properties = new HashMap<String,String[]>();
properties.put("options", []);
return properties
}
I am new to handling data in this format, any pointers will be good

I think this can do:
List<Map<String,String>> options = new ArrayList<Map<String,String>>();
and populate as :
Map<String, String> option1 = new HashMap<String, String>();
option1.put("value", "0");
option1.put("level", "zero");
options.add(option1);
Map<String, String> option2 = new HashMap<String, String>();
option2.put("value", "1");
option2.put("level", "one");
options.add(option2);
Map<String, String> option3 = new HashMap<String, String>();
option3.put("value", "2");
option3.put("level", "two");
options.add(option3);
EDIT: You can populate the list in a loop as below:
List<Map<String,String>> options = new ArrayList<Map<String,String>>();
String[] levels = {"zero", "one", "two"};
for(int indx = 0; indx <levels.length; indx++){
Map<String, String> option = new HashMap<String, String>();
option.put("value", String.valueOf(indx));
option.put("level", levels[indx]);
options.add(option);
}

Use this data structure:
List< Map<String, String> >

Filling Map - java

I have problem with filling a Map in Java, I think this is simple, but I can't resolve this.
Let's look at this:
Map<Integer, HashMap<String, String>> lineArrayData = new HashMap<Integer, HashMap<String, String>>();
HashMap<String, String> map = new HashMap<String, String>();
String singleData[];
int lineCounter = 0;
for ( String line : this.lines )
{
singleData = line.split("\\|\\|");
map.put("type", singleData[0]);
map.put("text", singleData[1]);
map.put("page", singleData[2]);
map.put("x", singleData[3]);
map.put("y", singleData[4]);
lineArrayData.put(lineCounter, map);
lineCounter++;
}
System.out.println(lineArrayData);
I have input
barcode||testowy test||1||100||100
text||texttstdasd||2||500||300
and my output is:
{0={text=texttstdasd, page=2, type=text, y=300, x=500}, 1={text=texttstdasd, page=2, type=text, y=300, x=500}}
what have I done wrong?

Move the following line inside the loop:
HashMap<String, String> map = new HashMap<String, String>();
Otherwise every iteration modifies the same inner map. The end result is that the outer map contains multiple references to the same inner map.
Here is the corrected version:
for ( String line : this.lines )
{
HashMap<String, String> map = new HashMap<String, String>();
singleData = line.split("\\|\\|");
...

Declare HashMap<String, String> map = new HashMap<String, String>(); inside the for loop.

You are using the same instance of the map in the loop. Also that should be
Map<Integer, Map<String, String>> lineArrayData = new HashMap<Integer, HashMap<String, String>>();
Map<String, String> map = new HashMap<String, String>();

Converting a Java Map object to a Properties object

Is anyone able to provide me with a better way than the below for converting a Java Map object to a Properties object?
Map<String, String> map = new LinkedHashMap<String, String>();
map.put("key", "value");
Properties properties = new Properties();
for (Map.Entry<String, String> entry : map.entrySet()) {
properties.put(entry.getKey(), entry.getValue());
}
Thanks

Use Properties::putAll(Map<String,String>) method:
Map<String, String> map = new LinkedHashMap<String, String>();
map.put("key", "value");
Properties properties = new Properties();
properties.putAll(map);

you also can use apache commons-collection4
org.apache.commons.collections4.MapUtils#toProperties(Map<K, V>)
example:
Map<String, String> map = new LinkedHashMap<String, String>();
map.put("name", "feilong");
map.put("age", "18");
map.put("country", "china");
Properties properties = org.apache.commons.collections4.MapUtils.toProperties(map);
see javadoc
https://commons.apache.org/proper/commons-collections/apidocs/org/apache/commons/collections4/MapUtils.html#toProperties(java.util.Map)

You can do this with Commons Configuration:
Properties props = ConfigurationConverter.getProperties(new MapConfiguration(map));
http://commons.apache.org/configuration

Try MapAsProperties from Cactoos:
import org.cactoos.list.MapAsProperties;
import org.cactoos.list.MapEntry;
Properties pros = new MapAsProperties(
new MapEntry<>("foo", "hello, world!")
new MapEntry<>("bar", "bye, bye!")
);

I got the idea from this article but I modified to convert from a Map to Properties. This is needed if you may need to manipulate the inputs.
Map<String,String> input = System.getenv();
Properties output = input.entrySet().stream().collect(
Collectors.toMap(
e -> String.valueOf(e.getKey()),
e -> String.valueOf(e.getValue()),
(prev, next) -> next, Properties::new
)
);
Also if you want to filter values from the Map.
Map<String,String> input = System.getenv();
Properties output = input.entrySet()
.stream().filter(e -> e.getKey().startsWith("XYZ")).collect(
Collectors.toMap(
e -> String.valueOf(e.getKey()),
e -> String.valueOf(e.getValue()),
(prev, next) -> next, Properties::new
)
);