Java应用DataOutputStream类和DataInputStream类将整型数据101长整型数据123456单精度浮点型数据31415926写入到desttxt文件中然后从该文件中读取数据并重新显示在屏幕上。‎

下面是Java代码示例：

import java.io.*;

public class DataStreamExample {
    public static void main(String[] args) {
        int intValue = 101;
        long longValue = 123456;
        float floatValue = 3.1415926f;
        String fileName = "dest.txt";
        
        try {
            // Write data to file
            FileOutputStream fos = new FileOutputStream(fileName);
            DataOutputStream dos = new DataOutputStream(fos);
            dos.writeInt(intValue);
            dos.writeLong(longValue);
            dos.writeFloat(floatValue);
            dos.close();
            
            // Read data from file
            FileInputStream fis = new FileInputStream(fileName);
            DataInputStream dis = new DataInputStream(fis);
            int readIntValue = dis.readInt();
            long readLongValue = dis.readLong();
            float readFloatValue = dis.readFloat();
            dis.close();
            
            // Display read data
            System.out.println("Read int value: " + readIntValue);
            System.out.println("Read long value: " + readLongValue);
            System.out.println("Read float value: " + readFloatValue);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

运行这段代码，将在屏幕上输出：

Read int value: 101
Read long value: 123456
Read float value: 3.1415927

请注意，读取的浮点数值可能略有不同，因为浮点数的精度有限