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Java

Posted by Mridul Gupta
Mridul Gupta
2,144 Points

Map inside a Map... How to load and store values from files using serialisation?

package com.ledgerProject.logic;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * Created by Mridul on 08-09-2015.
 */
public class User {
    private String mName;
    private Map<String, Map<String, List<Investment>>> mInvestmentMap;

    public User(String name) {
        this.mName = name;
        mInvestmentMap = new HashMap<>();
    }

    public String getName() {
        return mName;
    }

    public Map<String, Map<String, List<Investment>>> getInvestmentMap() {
        return mInvestmentMap;
    }

    public void insertToMap(String a, String b, Investment inv) {

        if (!mInvestmentMap.containsKey(a)) {
            List<Investment> list = new ArrayList<>();
            list.add(inv);
            Map<String, List<Investment>> innerMap = new HashMap<>();
            innerMap.put(b, list);
            mInvestmentMap.put(a, innerMap);
        } else if (!mInvestmentMap.get(a).containsKey(b)) {
            List<Investment> list = new ArrayList<>();
            list.add(inv);
            mInvestmentMap.get(a).put(b, list);
        } else {
            mInvestmentMap.get(a).get(b).add(inv);
        }

    }

    @Override
    public String toString() {
        return "User{" +
                "mName='" + mName + '\'' +
                ", mInvestmentMap=" + mInvestmentMap +
                '}';
    }

}

[Edited] So I think i wrote a function for insertion of value to my list inside the map inside a map. But now i want to load and store these values in files. Please need a little help in that.

Thanks a lot.

1 Answer

Mridul Gupta
Mridul Gupta
2,144 Points
Mridul Gupta
Mridul Gupta
2,144 Points 
    public void exportTo() {
        try (
                FileOutputStream fos = new FileOutputStream("/saves/" + mName + ".ser");
                ObjectOutputStream oos = new ObjectOutputStream(fos);
        ) {

            for (Map.Entry entry1 : mInvestmentMap.entrySet()) {
                Map<String,List<String>> innerMap = (Map<String, List<String>>) entry1.getValue();
                for (Map.Entry entry2 : )

            }
        }

I am doing something like this, but i could think what to write for the second for loop...Please help guys...Someone