Databases
StackOverflow2013
Postsdbo
PO[java]why hashmap's data come back after I add some data eventhough I hava already clear the hashmap
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO[java]why hashmap's data come back after I add some data eventhough I hava already clear the hashmap
    primarykey
    data
    text
    <pre><code>public class readBin { public static void main(String[] args) throws IOException{ long time1 = System.currentTimeMillis(); File targetfile = new File("d:\\d2012.bin"); FileInputStream in = new FileInputStream(targetfile); BufferedReader br = new BufferedReader(new InputStreamReader(in)); byte[] buffer = new byte[2097152]; int byteread = 0; String bufferString = ""; ArrayList&lt;HashMap&gt; arr = new ArrayList&lt;HashMap&gt;(); ArrayList arrstr = new ArrayList(); HashMap hashmap = new HashMap(); ArrayList&lt;String&gt; cttarr = new ArrayList&lt;String&gt;(); String[] strarr = new String[2]; ArrayList&lt;String&gt; valarr = new ArrayList&lt;&gt;(); //It's all init above,below comes the file reading bufferString = br.readLine(); while(bufferString != null){ //if data readed this line from the file is not "*newrecord" or "" if(!bufferString.equals("*NEWRECORD")&amp;&amp;!bufferString.equals("")){ //according to the need,make use of these data strarr = bufferString.split("="); switch (strarr[0].trim()) { case "UI": hashmap.put(strarr[0].trim(), strarr[1].trim()); break; case "MH": hashmap.put(strarr[0].trim(), strarr[1].trim()); break; case "AQ": String[] valuearr = strarr[1].split(" "); hashmap.put(strarr[0], valuearr); break; case "ENTRY": bufferString = bufferString.split("\\|")[0].toString(); //if key named ENTRY has already existed,update the data if (hashmap.containsKey(strarr[0].trim())) { ArrayList&lt;String&gt; templist = ((ArrayList&lt;String&gt;)hashmap.get(strarr[0].trim())); templist.add(bufferString.split("=")[1].trim()); hashmap.put(strarr[0].trim(), templist); //or insert it } else { cttarr.add(bufferString); hashmap.put(strarr[0].trim(),cttarr); } break; case "MS": hashmap.put(strarr[0].trim(), strarr[1].trim()); break; case "MN": //as ENTRY do if (hashmap.containsKey(strarr[0].trim())) { ArrayList&lt;String&gt; templist = ((ArrayList&lt;String&gt;)hashmap.get(strarr[0].trim())); templist.add(strarr[1].trim()); hashmap.put(strarr[0].trim(), templist); } else { cttarr.add(strarr[1].trim()); hashmap.put(strarr[0].trim(),cttarr); } break; default: break; } } else if(hashmap.size() != 0) { //if it equals to *newrecord or "",init the hashmap again arr.add(hashmap); hashmap = new HashMap(); } bufferString = br.readLine(); if (bufferString == null) { arr.add(hashmap); } } ArrayList arrresult = arr; long time2 = System.currentTimeMillis(); System.out.println(time2-time1); String ui = (String) arr.get(0).get("MH"); ArrayList&lt;String&gt; entrys = (ArrayList&lt;String&gt;) arr.get(0).get("ENTRY"); int len = arr.size(); System.out.println(ui); System.out.println(len); } public String getbs(){ return ""; } } </code></pre> <p>I want to iterate the data from the file and add them to the hashmap,after updating the hashmap to the arrayList,init the hashmap again.but from the result ,it seems the data in the hashmap wont clear.</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USuser1180629
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. PO[java]why hashmap's data come back after I add some data eventhough I hava already clear the hashmap
      1. This table or related slice is empty.
      1. VTDownMod
    2. VO
      singulars
      1. PO[java]why hashmap's data come back after I add some data eventhough I hava already clear the hashmap
      1. This table or related slice is empty.
      1. VTModeratorReview
    1. COAre you using java 7? and please elaborate your problem little more
      singulars
      1. PO[java]why hashmap's data come back after I add some data eventhough I hava already clear the hashmap
      1. USJigar Joshi
    2. COPlease provide more information otherwise it's hard to help
      singulars
      1. PO[java]why hashmap's data come back after I add some data eventhough I hava already clear the hashmap
      1. USTiago
    3. COyes，im using jdk 7.0
      singulars
      1. PO[java]why hashmap's data come back after I add some data eventhough I hava already clear the hashmap
      1. USuser1180629
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload