how to convert object to string in java

how to convert object to string in java

Im afraid your map contains something other than String objects. If you call toString() on a String object, you obtain the string itself.

What you get [Ljava.lang.String indicates you might have a String array.

Might not be so related to the issue above. However if you are looking for a way to serialize Java object as string, this could come in hand

package pt.iol.security;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import org.apache.commons.codec.binary.Base64;

public class ObjectUtil {

    static final Base64 base64 = new Base64();

    public static String serializeObjectToString(Object object) throws IOException {
        try (
                ByteArrayOutputStream arrayOutputStream = new ByteArrayOutputStream();
                GZIPOutputStream gzipOutputStream = new GZIPOutputStream(arrayOutputStream);
                ObjectOutputStream objectOutputStream = new ObjectOutputStream(gzipOutputStream);) {
            objectOutputStream.writeObject(object);
            objectOutputStream.flush();
            return new String(base64.encode(arrayOutputStream.toByteArray()));
        }
    }

    public static Object deserializeObjectFromString(String objectString) throws IOException, ClassNotFoundException {
        try (
                ByteArrayInputStream arrayInputStream = new ByteArrayInputStream(base64.decode(objectString));
                GZIPInputStream gzipInputStream = new GZIPInputStream(arrayInputStream);
                ObjectInputStream objectInputStream = new ObjectInputStream(gzipInputStream)) {
            return objectInputStream.readObject();
        }
    }
}

how to convert object to string in java

maybe you benefit from converting it to JSON string

String jsonString = new com.google.gson.Gson().toJson(myObject);

in my case, I wanted to add an object to the response headers but you cant add objects to the headers,

so to solve this I convert my object to JSON string and in the client side I will return that string to JSON again