linkedhashmap

问题 I want to build a parser to parse an XML file in Java . As you can see in my code below I am using a LinkedHashMap to access the desired values First , Middle and Last . My problem is that I have NameList tags containing multiple Person tags and the LinkedHashMap so far gives me only the last Person , in my example (output): given: Ghi family: Tom given: Jkl family: Mary How can I access the other two (Karl Abc, Thomas Def) using my approach with LinkedHashMap ? This is my XML file: <Sources>

问题 I have a file which contains lots of properties file line by line may be around 1000 and each properties file will be having around 5000 key-value pair. For eg:- Sample Example(abc.txt)- abc1.properties abc2.properties abc3.properties abc4.properties abc5.properties So I am opening this file and as it reads each line I am loading the properties file in loadProperties method. And storing key-value pair from that property in LinkedHashMap. public class Project { public static HashMap<String,

问题 I have a HashMap<String, LinkedHashMap<String,String> that is fairly long (not an issue) and I'm trying to make sure things look correct before I use the data inside it. To do this I'm trying to just attempting to do this Log.v("productsFromDB",products.toString()) but in the LogCat It shows about 1/3 of it. Is there a way to output the entire map? 回答1: Logcat can only show about 4000 characters. So you need to call a recursive function to see the entire hashmap. Try this function: public

问题 I am currently working on a project in which I am retrieving data about names from the Social Security website. Basically I'm given a number x, and years y and z. I have to return the top x names from each of the years y through z. So the data returned from the website is a name, a rank, and a year. I have to enter each name returned into either a TreeMap, HashMap, or LinkedHashMap, but I'm not sure how to store them, because no matter what I use as the key, there might be duplicates. The

问题 trying to make an lru map by subclassing linked hash map. the map is run through collections.synchronized. all usages of the map are surrounded by a synchronized block. the unit test also fails if they are all removed. one would think they are not necessary since the map was run through collections.synchronized. one thread puts sequential numbers (0,1,2,3 ...) into the map. removals are handled by removed eldest entry. no one else removes entries from the map. the other thread gets the data

问题 I use a method to get with volley my json object from server. The part that receives my object works fine, I get my response and I try to put my values into a linkedhashmap. When I try to return my map I get null . My method is like: public static LinkedHashMap<String,ArrayList<String>> GetBusinessInCategories() I declare my linkedhashmap outside method like: final static LinkedHashMap<String,ArrayList<String>> myMap = new LinkedHashMap<String,ArrayList<String>>(); public static LinkedHashMap

问题 As LinkedHashMap/Set keeps the order of entry in the Collection so it leads to a little lower performance. I want to know why this happens. 回答1: LinkedHash[Map/Set] use doubly linked lists to keep track of the order of entries. So whenever an element is added, a new DLL node must be created. The allocation takes time, and several extra pointers need to be set. 回答2: The question is making the invalid assumption that LinkedHash[Map/Set]s always perform worse than their non-linked counterparts.

问题 i have a program where i have to read data from excel file and store them in a database . I am using LinkedHashmap to read each cell as a string and store them. My excel file contains the data: ID Name Salary 43 paulina 1000 5 christine 2349000 54 laura 12587458 49 jim 45878 In my code I have made the fields for the table by the first row of the excel file and then I have filled the table with the rest of the data using again LinkedHashMap. My question is how in this step I can store the data

问题 LinkedHashMap looks brilliant to implement LRU Cache. It has some overheads in terms of linked list management and not thread safe but then it simplifies the implementation and I can take care of these in my code. The question I have, which I don't find answer so far about is how many elements LinkedHashMap removes from the list if removeEldestEntry is implemented and put finds the list full. Does it remove just one element? or some percentage of the total size. My concern is if it removes

问题 Is there any performance difference between HashMap and LinkedHashMap for traversal through values() function? 回答1: I think the LinkedHashMap has to be faster in traversal due to a superior nextEntry implementation in its Iterator Here is why : Let us go step by step from the values implementation. The HashMap implementation of values is this : public Collection<V> values() { Collection<V> vs = values; return (vs != null ? vs : (values = new Values())); } The LinkedHashMap extends from