Custom class should add by yourself. see https://github.com/node-modules/java.io#4-addobject

see unittest for a demo

http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/6-b14/java/util/Date.java#Date.writeObject%28java.io.ObjectOutputStream%29

impl writeObject and readObject

https://github.com/node-modules/java.io/blob/master/lib/objects/date.js#L5

I decode the timestamp class, the binary is not end with 0x78

        // if(!(tag == cons.TC_OBJECT)){
        //   assert.equal(tag, cons.TC_ENDBLOCKDATA,
        //     'SC_WRITE_METHOD object should end with TC_ENDBLOCKDATA');
        // }

this assert alway wrong, therefore i fork it and comment it.

raw.zip

Not sure adding Custom class can handle it

@Tsuki I try to handle readObject and use your raw.bin

  const io = require('java.io');

  io.addObject('java.sql.Timestamp', {
        readObject(io, obj) {
          console.log('>> java.sql.Timestamp readObject');
          io.readBlockHeader();

          var fastTime = io.readLong().toNumber();
          console.log('<< readObject | fastTime = %s', fastTime);

          obj._$ = new Date(fastTime);
          return obj;
        },

        writeObject(io, obj) {
          io.writeBlockHeader(8);
          io.writeLong(obj._$.getTime());
        },
      });

      var ret = io.ObjectInputStream.read(fs.readFileSync('raw.bin'), true);
      console.log(ret);

{
        '$': {},
        '$class':
         { name: 'java.sql.Timestamp',
           serialVersionUID: '2745179027874758501',
           flags: 2,
           fields: [ { type: 'I', name: 'nanos' } ],
           superClass:
            { name: 'java.util.Date',
              serialVersionUID: '7523967970034938905',
              flags: 3,
              fields: [],
              superClass: null } },
        '_$': new Date('2017-02-03T09:33:02.000Z'),
      }

It shoud be have nanos,

when you add io.defaultReadObject(obj);

you will get AssertionError: SC_WRITE_METHOD object should end with TC_ENDBLOCKDATA

{ '$': { nanos: 2015070607 },
  '$class': 
   { name: 'java.sql.Timestamp',
     serialVersionUID: '2745179027874758501',
     flags: 2,
     fields: [ [Object] ],
     superClass: 
      { name: 'java.util.Date',
        serialVersionUID: '7523967970034938905',
        flags: 3,
        fields: [],
        superClass: null } },
  '_$': 2017-02-03T09:44:05.000Z }

raw.zip

io.addObject('java.sql.Timestamp', {
  readObject(io, obj) {
    console.log('>> java.sql.Timestamp readObject');
    io.readBlockHeader();

    var fastTime = io.readLong().toNumber();
    console.log('<< readObject | fastTime = %s', fastTime);
    io.defaultReadObject(obj);
    obj._$ = new Date(fastTime);
    io.in.putInt8(120);
    io.in._offset--;
    return obj;
  },

  writeObject(io, obj) {
    io.writeBlockHeader(8);
    io.writeLong(obj._$.getTime());
  },
});

this is my workaround

{ '$': 
   { time: 
      { '$': [Object],
        '$class': [Object],
        '_$': 2017-02-06T01:45:15.000Z },
     time2: 
      { '$': [Object],
        '$class': [Object],
        '_$': 2017-02-06T01:45:15.000Z },
     time3: 
      { '$': [Object],
        '$class': [Object],
        '_$': 2017-02-06T01:45:15.000Z } },
  '$class': 
   { name: 'JavaObjectSerialiser$Test',
     serialVersionUID: '-7238052131403966026',
     flags: 2,
     fields: [ [Object], [Object], [Object] ],
     superClass: null } }