如何从用户数据类型的ArrayList创建字符串的ArrayList

Question

I have a ArrayList<MyDataType> pList; where MyDataType is a simple class like below:

class MyDataType {
    int modified;
    String name;
}

If my pList has size of 10 and if i want to retrieve ArrayList of names for all objects in it, how do I do that?

For example

ArrayList<String> myNames = new ArrayList<pList...>();

I want to know what the right hand side of the above statement should look like.

Answer 1

Declare a List<String> than iterate over pList and add name to names list .

 List<String> names=new ArrayList<>();
 for(MyDataType dt:pList){
 names.add(dt.getName())
 }

Answer 2

您将需要迭代pList并逐个添加每个名称。

Answer 3

List<String> names = new ArrayList<String>();

for(int i = 0; i < pList.size(); i++)
{
    names.add(pList.get(i).getName());
}

Answer 4

you can do like this

List<MyDataType > pList=new ArrayList<MyDataType >();

List<String> myNames = new ArrayList<String>();
for (MyDataType myDataType : pList) {           
    myNames.add(myDataType.getName());      
}

Answer 5

There are some functional ways to do this such as Guava, but that comes with some major performance concerns. Stick to the basics and iterate through the list.

List<String> names = new ArrayList<String>();
for(MyDataType element:pList){
    //hopefully this would use an accessor element.getName()
    names.add(element.name); 
}