Generate Tree Structure from Arrays Java
Question
I have an ArrayList of String arrays in java named:
List<String[]> initialList = new ArrayList<String[]>();
This contains the following data (This is a snippet of it, it actually includes about 900 rows that go on to include Charlie, Delta, Echo, each with the same structure as these:
[Alpha, A1, 1, null]
[Alpha, A1, 2, null]
[Alpha, A1, 3, null]
[Alpha, A1, 4, null]
[Alpha, A1, 5, null]
[Alpha, A1, 6, null]
[Alpha, A1, 7, null]
[Alpha, A1, 8, null]
[Alpha, A1, 9, null]
[Alpha, A1, 10, null]
[Alpha, A1, 11, null]
[Alpha, A1, 12, null]
[Alpha, A1, 13, null]
[Alpha, A1, 14, null]
[Alpha, A1, 15, null]
[Alpha, A1, 16, null]
[Alpha, A1, 17, null]
[Alpha, A1, 18, null]
[Alpha, A1, 19, null]
[Alpha, A1, 20, null]
[Alpha, A1, 21, null]
[Alpha, A1, 22, null]
[Alpha, A1, 23, null]
[Alpha, A1, 24, null]
[Alpha, A1, 25, null]
[Alpha, A1, 26, null]
[Alpha, A1, 27, null]
[Alpha, A1, 28, null]
[Alpha, A1, 29, null]
[Alpha, A1, 30, null]
[Alpha, A1, 31, null]
[Alpha, A1, 32, null]
[Alpha, A1, 33, null]
[Alpha, A1, 34, null]
[Alpha, A1, 35, null]
[Alpha, A1, 36, null]
[Alpha, A1, 37, null]
[Alpha, A1, 38, null]
[Alpha, A1, 39, null]
[Alpha, A1, 40, null]
[Alpha, A1, 41, null]
[Alpha, A1, 42, null]
[Alpha, A1, 43, null]
[Alpha, A1, 44, null]
[Alpha, A1, 45, null]
[Alpha, A1, 46, null]
[Alpha, A1, 47, null]
[Alpha, A1, 48, null]
[Alpha, A1, 49, null]
[Alpha, A1, 50, null]
[Alpha, A1, 51, null]
[Alpha, A1, 52, null]
[Alpha, A1, 53, null]
[Alpha, A1, 54, null]
[Alpha, A2, 1, null]
[Alpha, A2, 2, null]
[Alpha, A2, 3, null]
[Alpha, A2, 4, null]
[Alpha, A2, 5, null]
[Alpha, A2, 6, null]
[Alpha, A2, 7, null]
[Alpha, A2, 8, null]
[Alpha, A2, 9, null]
[Alpha, A2, 10, null]
[Alpha, A2, 11, null]
[Alpha, A2, 12, null]
[Alpha, A2, 13, null]
[Alpha, A2, 14, null]
[Alpha, A2, 15, null]
[Alpha, A2, 16, null]
[Alpha, A2, 17, null]
[Alpha, A2, 18, null]
[Alpha, A2, 19, null]
[Alpha, A2, 20, null]
[Alpha, A2, 21, null]
[Alpha, A2, 22, null]
[Alpha, A2, 23, null]
[Alpha, A2, 24, null]
[Alpha, A2, 25, null]
[Alpha, A2, 26, null]
[Alpha, A2, 27, null]
[Alpha, A2, 28, null]
[Alpha, A2, 29, null]
[Alpha, A2, 30, null]
[Alpha, A2, 31, null]
[Alpha, A2, 32, null]
[Alpha, A2, 33, null]
[Alpha, A2, 34, null]
[Alpha, A2, 35, null]
[Alpha, A2, 36, null]
[Alpha, A2, 37, null]
[Alpha, A2, 38, null]
[Alpha, A2, 39, null]
[Alpha, A2, 40, null]
[Alpha, A2, 41, null]
[Alpha, A2, 42, null]
[Alpha, A2, 43, null]
[Alpha, A2, 44, null]
[Alpha, A2, 45, null]
[Alpha, A2, 46, null]
[Alpha, A2, 47, null]
[Alpha, A2, 48, null]
[Alpha, A2, 49, null]
[Alpha, A2, 50, null]
[Alpha, A2, 51, null]
[Alpha, A2, 52, null]
[Alpha, A2, 53, null]
[Alpha, A2, 54, null]
[Alpha, A3, 1, null]
[Alpha, A3, 2, null]
[Alpha, A3, 3, null]
[Alpha, A3, 4, null]
[Alpha, A3, 5, null]
[Alpha, A3, 6, null]
[Alpha, A3, 7, null]
[Alpha, A3, 8, null]
[Alpha, A3, 9, null]
[Alpha, A3, 10, null]
[Alpha, A3, 11, null]
[Alpha, A3, 12, null]
[Alpha, A3, 13, null]
[Alpha, A3, 14, null]
[Alpha, A3, 15, null]
[Alpha, A3, 16, null]
[Alpha, A3, 17, null]
[Alpha, A3, 18, null]
[Alpha, A3, 19, null]
[Alpha, A3, 20, null]
[Alpha, A3, 21, null]
[Alpha, A3, 22, null]
[Alpha, A3, 23, null]
[Alpha, A3, 24, null]
[Alpha, A3, 25, null]
[Alpha, A3, 26, null]
[Alpha, A3, 27, null]
[Alpha, A3, 28, null]
[Alpha, A3, 29, null]
[Alpha, A3, 30, null]
[Alpha, A3, 31, null]
[Alpha, A3, 32, null]
[Alpha, A3, 33, null]
[Alpha, A3, 34, null]
[Alpha, A3, 35, null]
[Alpha, A3, 36, null]
[Alpha, A3, 37, null]
[Alpha, A3, 38, null]
[Alpha, A3, 39, null]
[Alpha, A3, 40, null]
[Alpha, A3, 41, null]
[Alpha, A3, 42, null]
[Alpha, A3, 43, null]
[Alpha, A3, 44, null]
[Alpha, A3, 45, null]
[Alpha, A3, 46, null]
[Alpha, A3, 47, null]
[Alpha, A3, 48, null]
[Alpha, A3, 49, null]
[Alpha, A3, 50, null]
[Alpha, A3, 51, null]
[Alpha, A3, 52, null]
[Alpha, A3, 53, null]
[Alpha, A3, 54, null]
[Alpha, A3, 55, null]
[Alpha, A3, 56, null]
[Alpha, A3, 57, null]
[Alpha, A3, 58, null]
[Alpha, A3, 59, null]
[Alpha, A3, 60, null]
[Alpha, A4, 1, null]
[Alpha, A4, 2, null]
[Alpha, A4, 3, null]
[Alpha, A4, 4, null]
[Alpha, A4, 5, null]
[Alpha, A4, 6, null]
[Alpha, A4, 7, null]
[Alpha, A4, 8, null]
[Alpha, A4, 9, null]
[Alpha, A4, 10, null]
[Alpha, A4, 11, null]
[Alpha, A4, 12, null]
[Alpha, A4, 13, null]
[Alpha, A4, 14, null]
[Alpha, A4, 15, null]
[Alpha, A4, 16, null]
[Alpha, A4, 17, null]
[Alpha, A4, 18, null]
[Alpha, A4, 19, null]
[Alpha, A4, 20, null]
[Alpha, A4, 21, null]
[Alpha, A4, 22, null]
[Alpha, A4, 23, null]
[Alpha, A4, 24, null]
[Alpha, A4, 25, null]
[Alpha, A4, 26, null]
[Alpha, A4, 27, null]
[Alpha, A4, 28, null]
[Alpha, A4, 29, null]
[Alpha, A4, 30, null]
[Alpha, A4, 31, null]
[Alpha, A4, 32, null]
[Alpha, A4, 33, null]
[Alpha, A4, 34, null]
[Alpha, A4, 35, null]
[Alpha, A4, 36, null]
[Alpha, A4, 37, null]
[Alpha, A4, 38, null]
[Alpha, A4, 39, null]
[Alpha, A4, 40, null]
[Alpha, A4, 41, null]
[Alpha, A4, 42, null]
[Alpha, A4, 43, null]
[Alpha, A4, 44, null]
[Alpha, A4, 45, null]
[Alpha, A4, 46, null]
[Alpha, A4, 47, null]
[Alpha, A4, 48, null]
[Alpha, A4, 49, null]
[Alpha, A4, 50, null]
[Alpha, A4, 51, null]
[Alpha, A4, 52, null]
[Alpha, A4, 53, null]
[Alpha, A4, 54, null]
[Alpha, A4, 55, null]
[Alpha, A4, 56, null]
[Alpha, A4, 57, null]
[Alpha, A4, 58, null]
[Alpha, A4, 59, null]
[Alpha, A4, 60, null]
[Bravo, B1, 1, null]
[Bravo, B1, 2, null]
[Bravo, B1, 3, null]
[Bravo, B1, 4, null]
[Bravo, B1, 5, null]
[Bravo, B1, 6, null]
[Bravo, B1, 7, null]
[Bravo, B1, 8, null]
[Bravo, B1, 9, null]
[Bravo, B1, 10, null]
[Bravo, B1, 11, null]
[Bravo, B1, 12, null]
[Bravo, B1, 13, null]
[Bravo, B1, 14, null]
[Bravo, B1, 15, null]
[Bravo, B1, 16, null]
[Bravo, B1, 17, null]
[Bravo, B1, 18, null]
[Bravo, B1, 19, null]
[Bravo, B1, 20, null]
[Bravo, B1, 21, null]
[Bravo, B1, 22, null]
[Bravo, B1, 23, null]
[Bravo, B1, 24, null]
[Bravo, B1, 25, null]
[Bravo, B1, 26, null]
[Bravo, B1, 27, null]
[Bravo, B1, 28, null]
[Bravo, B1, 29, null]
[Bravo, B1, 30, null]
[Bravo, B1, 31, null]
[Bravo, B1, 32, null]
[Bravo, B1, 33, null]
[Bravo, B1, 34, null]
[Bravo, B1, 35, null]
[Bravo, B1, 36, null]
[Bravo, B1, 37, null]
[Bravo, B1, 38, null]
[Bravo, B1, 39, null]
[Bravo, B1, 40, null]
[Bravo, B1, 41, null]
[Bravo, B1, 42, null]
[Bravo, B1, 43, null]
[Bravo, B1, 44, null]
[Bravo, B1, 45, null]
[Bravo, B1, 46, null]
[Bravo, B1, 47, null]
[Bravo, B1, 48, null]
[Bravo, B1, 49, null]
[Bravo, B1, 50, null]
[Bravo, B1, 51, null]
[Bravo, B1, 52, null]
[Bravo, B1, 53, null]
[Bravo, B1, 54, null]
[Bravo, B1, 55, null]
[Bravo, B1, 56, null]
[Bravo, B1, 57, null]
[Bravo, B1, 58, null]
[Bravo, B1, 59, null]
[Bravo, B1, 60, null]
[Bravo, B2, 1, null]
[Bravo, B2, 2, null]
[Bravo, B2, 3, null]
[Bravo, B2, 4, null]
[Bravo, B2, 5, null]
[Bravo, B2, 6, null]
[Bravo, B2, 7, null]
[Bravo, B2, 8, null]
[Bravo, B2, 9, null]
[Bravo, B2, 10, null]
[Bravo, B2, 11, null]
[Bravo, B2, 12, null]
[Bravo, B2, 13, null]
[Bravo, B2, 14, null]
[Bravo, B2, 15, null]
[Bravo, B2, 16, null]
[Bravo, B2, 17, null]
[Bravo, B2, 18, null]
[Bravo, B2, 19, null]
[Bravo, B2, 20, null]
[Bravo, B2, 21, null]
[Bravo, B2, 22, null]
[Bravo, B2, 23, null]
[Bravo, B2, 24, null]
[Bravo, B2, 25, null]
[Bravo, B2, 26, null]
[Bravo, B2, 27, null]
[Bravo, B2, 28, null]
[Bravo, B2, 29, null]
[Bravo, B2, 30, null]
[Bravo, B2, 31, null]
[Bravo, B2, 32, null]
[Bravo, B2, 33, null]
[Bravo, B2, 34, null]
[Bravo, B2, 35, null]
[Bravo, B2, 36, null]
[Bravo, B2, 37, null]
[Bravo, B2, 38, null]
[Bravo, B2, 39, null]
[Bravo, B2, 40, null]
[Bravo, B2, 41, null]
[Bravo, B2, 42, null]
[Bravo, B2, 43, null]
[Bravo, B2, 44, null]
[Bravo, B2, 45, null]
[Bravo, B2, 46, null]
[Bravo, B2, 47, null]
[Bravo, B2, 48, null]
[Bravo, B2, 49, null]
[Bravo, B2, 50, null]
[Bravo, B2, 51, null]
[Bravo, B2, 52, null]
[Bravo, B2, 53, null]
[Bravo, B2, 54, null]
[Bravo, B2, 55, null]
[Bravo, B2, 56, null]
[Bravo, B2, 57, null]
[Bravo, B2, 58, null]
[Bravo, B2, 59, null]
[Bravo, B2, 60, null]
[Bravo, B3, 1, null]
[Bravo, B3, 2, null]
[Bravo, B3, 3, null]
[Bravo, B3, 4, null]
[Bravo, B3, 5, null]
[Bravo, B3, 6, null]
[Bravo, B3, 7, null]
[Bravo, B3, 8, null]
[Bravo, B3, 9, null]
[Bravo, B3, 10, null]
[Bravo, B3, 11, null]
[Bravo, B3, 12, null]
[Bravo, B3, 13, null]
[Bravo, B3, 14, null]
[Bravo, B3, 15, null]
[Bravo, B3, 16, null]
[Bravo, B3, 17, null]
[Bravo, B3, 18, null]
[Bravo, B3, 19, null]
[Bravo, B3, 20, null]
[Bravo, B3, 21, null]
[Bravo, B3, 22, null]
[Bravo, B3, 23, null]
[Bravo, B3, 24, null]
[Bravo, B3, 25, null]
[Bravo, B3, 26, null]
[Bravo, B3, 27, null]
[Bravo, B3, 28, null]
[Bravo, B3, 29, null]
[Bravo, B3, 30, null]
[Bravo, B3, 31, null]
[Bravo, B3, 32, null]
[Bravo, B3, 33, null]
[Bravo, B3, 34, null]
[Bravo, B3, 35, null]
[Bravo, B3, 36, null]
[Bravo, B3, 37, null]
[Bravo, B3, 38, null]
[Bravo, B3, 39, null]
[Bravo, B3, 40, null]
[Bravo, B3, 41, null]
[Bravo, B3, 42, null]
[Bravo, B3, 43, null]
[Bravo, B3, 44, null]
[Bravo, B3, 45, null]
[Bravo, B3, 46, null]
[Bravo, B3, 47, null]
[Bravo, B3, 48, null]
[Bravo, B3, 49, null]
[Bravo, B3, 50, null]
[Bravo, B3, 51, null]
[Bravo, B3, 52, null]
[Bravo, B3, 53, null]
The structure is as follows: Alpha, Bravo, Charlie, Delta, and Echo are root nodes that hold: (A1, A2, A3, A4) (B1, B2, B3, B4) (C1, C2, C3, C4) ect... which then each hold a 'n' number of spots where each number holds a persons name.
I need to make this into a Hierarchical Tree Structure. I have tried the following:
Map<String, Set<String>> myNodes = new LinkedHashMap<String, Set<String>>();
for(String[] myArray : initialList) {
String previousNode = null;
for(String node : myArray) {
if(myNodes.get(node) == null) {
myNodes.put(node, new HashSet<String>());
}
if(previousNode != null) {
myNodes.get(previousNode).add(node);
}
previousNode = node;
}
}
But this outputs as follows, which as you can see is wrong and not what I am looking for (again, just a snippet of the full output).
Alpha : [A2, A1, A4, A3]
A1 : [35, 36, 33, 34, 39, 37, 38, 43, 42, 41, 40, 22, 23, 24, 25, 26, 27, 28, 29, 3, 2, 1, 7, 30, 6, 5, 32, 4, 31, 9, 8, 19, 17, 18, 15, 16, 13, 14, 11, 12, 21, 20, 49, 48, 45, 44, 47, 46, 10, 51, 52, 53, 54, 50]
1 : [null]
null : []
2 : [null]
null : []
3 : [null]
4 : [null]
5 : [null]
6 : [null]
7 : [null]
8 : [null]
9 : [null]
10 : [null]
11 : [null]
12 : [null]
13 : [null]
14 : [null]
15 : [null]
16 : [null]
17 : [null]
18 : [null]
19 : [null]
20 : [null]
21 : [null]
22 : [null]
23 : [null]
24 : [null]
25 : [null]
26 : [null]
27 : [null]
28 : [null]
29 : [null]
30 : [null]
31 : [null]
32 : [null]
33 : [null]
34 : [null]
35 : [null]
36 : [null]
37 : [null]
38 : [null]
39 : [null]
40 : [null]
41 : [null]
42 : [null]
43 : [null]
44 : [null]
45 : [null]
46 : [null]
47 : [null]
48 : [null]
49 : [null]
50 : [null]
51 : [null]
52 : [null]
53 : [null]
54 : [null]
A2 : [35, 36, 33, 34, 39, 37, 38, 43, 42, 41, 40, 22, 23, 24, 25, 26, 27, 28, 29, 3, 2, 1, 7, 30, 6, 5, 32, 4, 31, 9, 8, 19, 17, 18, 15, 16, 13, 14, 11, 12, 21, 20, 49, 48, 45, 44, 47, 46, 10, 51, 52, 53, 54, 50]
A3 : [35, 36, 33, 34, 39, 37, 38, 43, 42, 41, 40, 22, 23, 24, 25, 26, 27, 28, 29, 3, 2, 1, 7, 30, 6, 5, 32, 4, 31, 9, 8, 59, 58, 57, 56, 19, 55, 17, 18, 15, 16, 13, 14, 11, 12, 21, 20, 60, 49, 48, 45, 44, 47, 46, 10, 51, 52, 53, 54, 50]
55 : [null]
56 : [null]
57 : [null]
58 : [null]
59 : [null]
60 : [null]
A4 : [35, 36, 33, 34, 39, 37, 38, 43, 42, 41, 40, 22, 23, 24, 25, 26, 27, 28, 29, 3, 2, 1, 7, 30, 6, 5, 32, 4, 31, 9, 8, 59, 58, 57, 56, 19, 55, 17, 18, 15, 16, 13, 14, 11, 12, 21, 20, 60, 49, 48, 45, 44, 47, 46, 10, 51, 52, 53, 54, 50]
Bravo : [B4, B3, B2, B1]
B1 : [35, 36, 33, 34, 39, 37, 38, 43, 42, 41, 40, 22, 23, 24, 25, 26, 27, 28, 29, 3, 2, 1, 7, 30, 6, 5, 32, 4, 31, 9, 8, 59, 58, 57, 56, 19, 55, 17, 18, 15, 16, 13, 14, 11, 12, 21, 20, 60, 49, 48, 45, 44, 47, 46, 10, 51, 52, 53, 54, 50]
B2 : [35, 36, 33, 34, 39, 37, 38, 43, 42, 41, 40, 22, 23, 24, 25, 26, 27, 28, 29, 3, 2, 1, 7, 30, 6, 5, 32, 4, 31, 9, 8, 59, 58, 57, 56, 19, 55, 17, 18, 15, 16, 13, 14, 11, 12, 21, 20, 60, 49, 48, 45, 44, 47, 46, 10, 51, 52, 53, 54, 50]
B3 : [35, 36, 33, 34, 39, 37, 38, 43, 42, 41, 40, 22, 23, 24, 25, 26, 27, 28, 29, 3, 2, 1, 7, 30, 6, 5, 32, 4, 31, 9, 8, 59, 58, 57, 56, 19, 55, 17, 18, 15, 16, 13, 14, 11, 12, 21, 20, 60, 49, 48, 45, 44, 47, 46, 10, 51, 52, 53, 54, 50]
B4 : [35, 36, 33, 34, 39, 37, 38, 43, 42, 41, 40, 22, 23, 24, 25, 26, 27, 28, 29, 3, 2, 1, 7, 30, 6, 5, 32, 4, 31, 9, 8, 59, 58, 57, 56, 19, 55, 17, 18, 15, 16, 13, 14, 11, 12, 21, 20, 60, 49, 48, 45, 44, 47, 46, 10, 51, 52, 53, 54, 50]
This was using a Map and LinkedHashMap, so I also tried it with a TreeMap (not even sure if this is what I need though):
TreeMap<String, Set<String>> myNodes = new TreeMap<String, Set<String>>();
for(String[] myArray : initialList) {
String previousNode = null;
for(String node : myArray) {
if(myNodes.get(node) == null) {
myNodes.put(node, new HashSet<String>());
}
if(previousNode != null) {
myNodes.get(previousNode).add(node);
}
previousNode = node;
}
}
But got the following error:
Exception in thread "main" java.lang.NullPointerException
at java.util.TreeMap.getEntry(TreeMap.java:324)
at java.util.TreeMap.get(TreeMap.java:255)
I need it hierarchical as I described above. I would love to describe exactly what it should output, but truthfully, I am not sure, I just know it needs to have a heirarchy structure and converted to JSON as described below.
Also, this must be converted to JSON in the following format so please keep that in mind (again, actual output is much larger, this is simply a structure example:
{
"name":"Alpha",
"children":[
{
"name":"A1",
"children":[
{
"name":"1",
"children":[
{
"name":"null",
},
]
"name":"2",
"children":[
{
"name":"null",
},
]
"name":"3",
"children":[
{
"name":"null",
},
]
},
"name":"A2",
"children":[
{
"name":"1",
"children":[
{
"name":"null",
},
]
"name":"2",
"children":[
{
"name":"null",
},
]
"name":"3",
"children":[
{
"name":"null",
},
]
},
]
},
I would appreciate any help I can get because I am truly stumped. Thanks!
2 answers
solution1
2 ACCPTED 2015-03-10 20:27:13
Try running the following code.
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
class JsonModel {
private String name;
private List<JsonModel> children;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public List<JsonModel> getChildren() {
return children;
}
public void setChildren(List<JsonModel> children) {
this.children = children;
}
public String toString(){
return "name: "+name + ", children: {"+children+"}";
}
}
public class Test{
public static void main(String a[])
{
ArrayList<String[]> initialList= new ArrayList<String[]>();
initialList.add(new String[]{"Alpha", "A1", "1", null});
initialList.add(new String[]{"Alpha", "A1", "2", null});
initialList.add(new String[]{"Alpha", "A2", "1", null});
initialList.add(new String[]{"Alpha", "A2", "2", null});
initialList.add(new String[]{"Beta", "A1", "1", null});
initialList.add(new String[]{"Beta", "A1", "2", null});
initialList.add(new String[]{"Beta", "A2", "1", null});
initialList.add(new String[]{"Beta", "A2", "2", null});
ArrayList<JsonModel> returnList = new ArrayList<JsonModel>();
HashMap<String,HashMap<String,JsonModel>> tempMap = new HashMap<String, HashMap<String,JsonModel>>();
HashMap<String,JsonModel> tempMapOuterMost = new HashMap<String, JsonModel>();
// eg. 1,null
JsonModel layer3Child = null;
// eg. A1,{}
JsonModel layer2Child = null;
// eg. Alpha,{}
JsonModel layer1Child = null;
for(String[] myArray: initialList){
// to set inner most object eg. 1,null
layer3Child = new JsonModel();
layer3Child.setName(myArray[2]);
JsonModel layer4Child = new JsonModel();
layer4Child.setName("PersonName");
ArrayList<JsonModel> layer4Children = new ArrayList<JsonModel>();
layer4Children.add(layer4Child);
layer3Child.setChildren(layer4Children);
// getting object of outermost model eg. Alpha,{}
if (tempMap.containsKey(myArray[0])){
layer1Child = tempMapOuterMost.get(myArray[0]);
} else {
layer1Child = new JsonModel();
layer1Child.setName(myArray[0]);
layer1Child.setChildren(new ArrayList<JsonModel>());
returnList.add(layer1Child);
tempMapOuterMost.put(myArray[0], layer1Child);
tempMap.put(myArray[0], new HashMap<String,JsonModel>());
}
// getting the object at layer 2 eg. A1,{}
if (tempMap.get(myArray[0]).containsKey(myArray[1])){
layer2Child = tempMap.get(myArray[0]).get(myArray[1]);
} else {
layer2Child = new JsonModel();
layer2Child.setName(myArray[1]);
layer2Child.setChildren(new ArrayList<JsonModel>());
layer1Child.getChildren().add(layer2Child);
tempMap.get(myArray[0]).put(myArray[1], layer2Child);
}
layer2Child.getChildren().add(layer3Child);
}
System.out.println(returnList);
}
}
solution2
0 2015-03-10 19:24:35
Here is a really rough implementation of a basic Tree. It could use a bunch more improvements, like string builder, and generics.
Also you should look at this question and answers: Java tree data-structure?
I would also recommend reading a Data structures book like this: https://books.google.com/books?id=GEJ_Jp6mUpgC&dq=data+structures&source=gbs_navlinks_s
public Tree
{
public String value;
public List<Tree> children;
public Tree(String value)
{
children = new ArrayList();
this.value = value;
}
public void AddChild(Tree child)
{
children.Add(child);
}
public String ToString()
{
String fullString = value;
for(Tree child : children)
{
fullString += "\n";
fullString += child.ToString();
}
return fullString;
}
}
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