arraylist

Sorting an ArrayList of Objects alphabetically

由 徘徊边缘 提交于 2019-12-20 10:00:24
问题 I have to create a method that sorts an ArrayList of objects alphabetically according to email and then prints the sorted array. The part that I am having trouble with it sorting it. I have researched it and tried using Collections.sort(vehiclearray); but that didn't work for me. I was that I needed something called a comparator but couldn't figure out how it worked. Will I have to use those or can something like bubble sort or insertion sort work for this kind of thing? This is the code that

Retrieve all values from HashMap keys in an ArrayList Java

由 霸气de小男生 提交于 2019-12-20 09:29:47
问题 Good day, this is kind of confusing me now(brain freeze!) and seem to be missing something. Have an ArrayList which i populate with a HashMap. now i put in my HashMap and arraylist. Map.put(DATE, value1); Map.put(VALUE, value2); arraylist.put(Map); Since am parsing a JSON, the arraylist increases in significant size. now my question is how do you get the values from both map keys in the arraylist? i have tried this if(!list.isEmpty()){ // list is an ArrayList for(int k = 0; k < list.size(); k

Retrieving an element from array list in Android?

由 拜拜、爱过 提交于 2019-12-20 09:18:00
问题 I am trying to implement voice recognition code in Android. How do I get an element at a particular position from array list in Android? I tried converting arraylist to array and retriving. Still the code is not working. package com.espeaker; public class EspeakerActivity extends Activity { private static final int REQUEST_CODE = 1234; private ListView wordsList; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate

Convert ForeignCollection to ArrayList - ORMLite, Gson and Android

由 时光怂恿深爱的人放手 提交于 2019-12-20 09:14:35
问题 I apologize if I'm not super clear with my explanation but I'll add to and edit this question for clarity if requested. I am developing an Android app which receives data through an external API and stores data locally using ORMLite. Prior to storing data locally and using ORMLite I had models which retrieved JSON from the server and parsed it via: Gson gson = new Gson(); String result = ApiClient.httpPost("/user_route"); User user = gson.fromJson(result, User.class); The User class was

Convert ForeignCollection to ArrayList - ORMLite, Gson and Android

由 六月ゝ 毕业季﹏ 提交于 2019-12-20 09:14:00
问题 I apologize if I'm not super clear with my explanation but I'll add to and edit this question for clarity if requested. I am developing an Android app which receives data through an external API and stores data locally using ORMLite. Prior to storing data locally and using ORMLite I had models which retrieved JSON from the server and parsed it via: Gson gson = new Gson(); String result = ApiClient.httpPost("/user_route"); User user = gson.fromJson(result, User.class); The User class was

simple conditional in java (unexpected issue)

由 血红的双手。 提交于 2019-12-20 08:11:07
问题 I have an unexpected issue when using a conditional operator in java. The code is supposed to check if the ArrayList contains a specific string, then it returns true or false. It is not the first time I do this, but for some reason there's something wrong. This is my code so far: public boolean isDone() { ArrayList<String> al = new ArrayList<String>(); //Defining ArrayList al.add(d1.getText()); // Adding the text from JLabels. al.add(d2.getText()); al.add(d3.getText()); al.add(d4.getText());

simple conditional in java (unexpected issue)

由 瘦欲@ 提交于 2019-12-20 08:11:06
问题 I have an unexpected issue when using a conditional operator in java. The code is supposed to check if the ArrayList contains a specific string, then it returns true or false. It is not the first time I do this, but for some reason there's something wrong. This is my code so far: public boolean isDone() { ArrayList<String> al = new ArrayList<String>(); //Defining ArrayList al.add(d1.getText()); // Adding the text from JLabels. al.add(d2.getText()); al.add(d3.getText()); al.add(d4.getText());

How to pick up only integer data from an ArrayList of String

由 夙愿已清 提交于 2019-12-20 07:48:45
问题 I read a text file and put the data into an ArrayList of String . The data is like China 12351235123 Korea 123532523 USA 12341235123 I just need those integer data as an integer to find the first digit of the integers. I know how to find the first digit, but I don't know how I can pick up only the integer data. 回答1: I am assuming that your ArrayList is of type String . replaceAll() will take out anything that isn't a number(0-9) ArrayList<String> countrys = new ArrayList<String>(); countrys

UML第二次作业

由 五迷三道 提交于 2019-12-20 07:47:09
一、plant UML语法学习小结 1.类之间的关系 使用 .. 来代替 -- 可以得到点 线. 在这些规则下，也可以绘制下列图形 @startumlClass01 <|-- Class02 Class03 *-- Class04 Class05 o-- Class06 Class07 .. Class08 Class09 -- Class10 @enduml @startuml Class11 <|.. Class12 Class13 --> Class14 Class15 ..> Class16 Class17 ..|> Class18 Class19 <--* Class20 @enduml @startuml Class21 #-- Class22 Class23 x-- Class24 Class25 }-- Class26 Class27 +-- Class28 Class29 ^-- Class30 @enduml 2、关系上的标识 在关系之间使用标签来说明时, 使用 : 后接 标签文字。 对元素的说明，你可以在每一边使用 "" 来说明. @startuml Class01 "1" *-- "many" Class02 : contains Class03 o-- Class04 : aggregation Class05 --> "1" Class06

Adding only specific text from a file to an array list, part 2 - Java

由 陌路散爱 提交于 2019-12-20 07:39:50
问题 I hope I can have some great suggestion how I can solve this here: I have this text file with places and names - name detail indicates the place(s) that the person has visited: Place: New York Place: London Place: Paris Place: Hongkong 1. Name: John 1. Name detail: London 1. Name detail: Paris 1. Name detail: Hongkong 2. Name: Sarah 2. Name detail: London 3. Name: David 3. Name detail: New York 3. Name detail: Paris Here is a part of my code. private ArrayList<Place> places = new ArrayList<>(
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