我有數據在以下格式卸下值
String [] data = new String[]{"-166444026 0 file 20130801",
"-166444026 0 file 20130802",
"-166444027 0 file 20130802"};
這些選項卡分隔字符串。 現在.. 所以我們有 鍵,值,類型,日期。
我想要的是保持列表中最新的唯一鍵。 因此,例如... 這個操作的輸出應該是...
["-166444026 0 file 20130802",
"-166444027 0 file 20130802"];
因爲-166444026出現兩次,但一個我刪除有20130801日期和這其中有一個較後日期?
我寫的代碼..但這只是返回一切。(我認爲這是假設刪除..但它沒有..)?? ??
任何線索?
package org.random_scripts;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.json.simple.JSONObject;
public class Regex {
private static boolean alreadyExists(Map<String, Long> dict, String key) {
if(dict.containsKey(key))
return true;
return false;
}
private static void removeEdge(ArrayList<JSONObject>edgeList, String key) {
for(JSONObject edge:edgeList) {
if (edge.get("destination").equals(key))
edge.remove(key);
}
}
public static void main(String[] args) {
String [] data = new String[]{"-166444026 0 file 20130801",
"-166444026 0 file 20130802",
"-166444026 0 file 20130802"};
try {
String key = "185479485";
JSONObject jsn = new JSONObject();
jsn.put("source", key.toString());
ArrayList<JSONObject> edges = new ArrayList<JSONObject>();
Map<String, Long> tracker = new HashMap<String, Long>();
for (int i=0; i < data.length; i++) {
String value = data[i];
//edgeString+= value.toString()+",";
String[] typeChunks = value.toString().split("\t");
String destination = typeChunks[0];
Double reputation = Double.parseDouble(String.valueOf(typeChunks[1]));
System.out.println(tracker.values().toString());
JSONObject edgeJson = new JSONObject();
Long date = Long.valueOf(typeChunks[3]);
if(alreadyExists(tracker,destination)) {
Long prev_date = tracker.get(destination);
System.out.println(true);
if (date > prev_date) {
//remove edge
removeEdge(edges,destination);
System.out.println("edges are" + edges.toString());
}
}
else {
tracker.put(destination, date);
}
edgeJson.put("destination", destination);
edgeJson.put("reputation", reputation);
edgeJson.put("type", typeChunks[2]);
edges.add(edgeJson);
}
jsn.put("edgelist", edges);
System.out.println(jsn.toJSONString());
//context.write(NullWritable.get(), new Text(jsn.toJSONString()));
//edgeString = edgeString.substring(0,edgeString.length()-1);
//edgeString+="]";
}
catch (Exception e) {
System.out.println("Exceptiom");
//context.write(NullWritable.get(),new Text(s));
}
}
}