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How to write serializable object to String without writing to file?

I want to write a class object to the string and then again create an object from it.
I searched on the net but all I found is to write an object to file however I want to write in the string, not on file.
Below is the example of writing to file similarly I want to write in String or similar Object and not in the file.
some_class implements serializable {
...
}
FileOutputStream f = new FileOutputStream(new File("myObjects.txt"));
ObjectOutputStream o = new ObjectOutputStream(f);
// Write objects to file
o.writeObject(object1);
o.close();
f.close();
FileInputStream fi = new FileInputStream(new File("myObjects.txt"));
ObjectInputStream oi = new ObjectInputStream(fi);
// Read objects
some_class object2 = (some_class) oi.readObject();
oi.close();
fi.close();
Please help with the same.

This would be one way:
try
{
// To String
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream os = new ObjectOutputStream(bos);
os.writeObject(object1);
String serializedObject1 = bos.toString();
os.close();
// To Object
ByteArrayInputStream bis = new ByteArrayInputStream(serializedObject1.getBytes());
ObjectInputStream oInputStream = new ObjectInputStream(bis);
YourObject restoredObject1 = (YourObject) oInputStream.readObject();
oInputStream.close();
} catch(Exception ex) {
ex.printStackTrace();
}
I would prefer the Base64 way though.
This would be an example of encoding:
private static String serializableToString( Serializable o ) throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(baos);
oos.writeObject(o);
oos.close();
return Base64.getEncoder().encodeToString(baos.toByteArray());
}
And this is an example of decoding:
private static Object objectFromString(String s) throws IOException, ClassNotFoundException
{
byte [] data = Base64.getDecoder().decode(s);
ObjectInputStream ois = new ObjectInputStream(
new ByteArrayInputStream(data));
Object o = ois.readObject();
ois.close();
return o;
}

the best way to serialize an object to String and vice versa you should convert the object into JSON String and encode into base64. and to get object decode base64 and convert to object using GSON (opensource google provide java library)
class foo{ String name, email;
//setter getter
}
convert Object to base64 JSON
public static String convertToJson(Object o){
String result=new Gson().toJson(o);
return Base64.getEncoder().encodeToString(result);
}
//read base64
public static <T> T convertJsonToObject(String base64Object,Class<T> classOfT){
Gson gson = new Gson();
return gson.fromJson(new InputStreamReader(new ByteArrayInputStream(Base64.getDecoder().decode(base64Object))),classOfT);
}
public static void main(String[] args) {
foo obj=new foo("jhon","jhon#gamil.com");
String json=convertToJson(foo);
System.out.println(json);
foo obj_fromJson=convertJsonToObject(json,foo.class);
System.out.println(obj_fromJson.getName());
}

Unclosed Objects Alerts in CheckMarx scan

I have run SAST in my codebase and got some Medium severity alerts in the Checkmarx scan and few of them states 'Unclosed_Objects' . I am not understanding this issue. Any pointers will help me.
This is giving alerts in this section of the code. All the close() methods.
public Object deepCopy(final Object value) throws HibernateException {
try {
// use serialization to create a deep copy
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(value);
oos.flush();
oos.close();
bos.close();
ByteArrayInputStream bais = new ByteArrayInputStream(bos.toByteArray());
Object obj = new ObjectInputStream(bais).readObject();
bais.close();
return obj;
} catch (ClassNotFoundException | IOException ex) {
throw new HibernateException(ex);
}

Java - How to do Gzip compression of java object

How to compress a Java pojo object using Gzip?
Below code compress a string -
public static String compress(String str, String inEncoding) {
if (str == null || str.length() == 0) {
return str;
}
try {
ByteArrayOutputStream out = new ByteArrayOutputStream();
GZIPOutputStream gzip = new GZIPOutputStream(out);
gzip.write(str.getBytes(inEncoding));
gzip.close();
return URLEncoder.encode(out.toString("ISO-8859-1"), "UTF-8");
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
Instead of String str as a parameter, how to use below pojo class object (Client cc) and compress?
Pojo class -
Class client {
Public string name;
Public string location;
//Getter and setter methods
}
How can i compress and decompress this client pojo class using gzip.?

You can compress your Client class which implements serializable using gzip by doing the following :
public static bytes[] compressThis(Client client){
ByteArrayOutputStream baos = new ByteArrayOutputStream();
GZIPOutputStream gzipOut = new GZIPOutputStream(client);
ObjectOutputStream objectOut = new ObjectOutputStream(gzipOut);
objectOut.writeObject(client);
objectOut.close();
return baos.toByteArray();
}
Following which you can decompress it by doing the following :
public static getClientFrom(bytes[] bytes){
ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
GZIPInputStream gzipIn = new GZIPInputStream(bais);
ObjectInputStream objectIn = new ObjectInputStream(gzipIn);
Client client = (Client) objectIn.readObject();
objectIn.close();
return client;
}

ObjectInputStream throwing exception on read

I'm having difficulty with ObjectInputStream. I wrote a simple test which fails on the read with an EOF error. Any input would be greatly appreciated.
public class Test
{
#Test
public void testObjectStreams( ) throws IOException, ClassNotFoundException
{
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(baos);
String stringTest = "TEST";
oos.writeObject( stringTest );
oos.close();
baos.close();
byte[] bytes = baos.toByteArray();
String hexString = DatatypeConverter.printHexBinary( bytes);
byte[] reconvertedBytes = DatatypeConverter.parseHexBinary(hexString);
assertArrayEquals( bytes, reconvertedBytes );
ByteArrayInputStream bais = new ByteArrayInputStream(reconvertedBytes);
ObjectInputStream ois = new ObjectInputStream(bais);
String readString = (String) ois.readObject();
assertEquals( stringTest, readString);
}
}

Serialization and archiving object

I need to do the same operation but in one stream. May you help me, please?
public static byte[] archivingAndSerialization(Object object){
ByteArrayOutputStream serializationByteArray = new ByteArrayOutputStream();
ByteArrayOutputStream archvingByteArray = new ByteArrayOutputStream();
try {
ObjectOutputStream byteStream = new ObjectOutputStream(serializationByteArray);
byteStream.writeObject(object);
ZipOutputStream out = new ZipOutputStream(archvingByteArray);
out.putNextEntry(new ZipEntry("str"));
out.write(serializationByteArray.toByteArray());
out.flush();
out.close();
} catch (IOException e) {
logger.error("Error while IOException!", e);
}
return archvingByteArray.toByteArray();
}

Try
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos= new ObjectOutputStream(new DeflatingOutputStream(baos));
oos.writeObject(object);
oos.close();
return baos.toByteArray();
Note: Unless the object is medium to large in size, compressing it will make it bigger, as it add a header. ;)
To deserialize
ObjectInputStream ois = new ObjectInputStream(
new InflatorInputStream(new ByteArrayInputStream(bytes)));
return ois.readObject();