abstract int get(String name, int val) abstract float get(String name, float val) abstract long get(String name, long val) 描述 该 java.io.ObjectInputStream.getField.get(String name, int val)方法获取指定的int字段从持久字段的值。 声明 以下是java.io.ObjectInputStream.getField.get()方法的声明。 public abstract int get(String name, int val) 参数 name - 字段的名称。 val - 如果name没有值,则使用默认值。 返回值 此方法返回指定的int字段的值。 异常 IOException - 如果从底层InputStream读取时存在I / O错误。 IllegalArgumentException - 如果name的类型不可序列化或字段类型不正确。 实例 以下示例显示了java.io.ObjectInputStream.getField.get()方法的用法。 package com.tutorialspoint; import java.io.*; public class ObjectInputStreamDemo implements Serializable { public static void main(String[] args) { try { // create a new file with an ObjectOutputStream FileOutputStream out = new FileOutputStream("test.txt"); ObjectOutputStream oout = new ObjectOutputStream(out); // write something in the file oout.writeObject(new Example()); oout.flush(); oout.close(); // create an ObjectInputStream for the file we created before ObjectInputStream ois = new ObjectInputStream(new FileInputStream("test.txt")); // read an object from the stream and cast it to Example Example a = (Example) ois.readObject(); // print var of a System.out.println("" + a.var); } catch (Exception ex) { ex.printStackTrace(); } } static public class Example implements Serializable { static int var = 76458; // assign a new serialPersistentFields private static final ObjectStreamField[] serialPersistentFields = { new ObjectStreamField("var", Integer.TYPE) }; private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { // get the field and assign it at var ObjectInputStream.GetField fields = in.readFields(); // get var var = fields.get("var", 0); } private void writeObject(ObjectOutputStream out) throws IOException { // write into the ObjectStreamField array the variable string ObjectOutputStream.PutField fields = out.putFields(); fields.put("var", var); out.writeFields(); } } } 让我们编译并运行上面的程序,这将产生以下结果 76458 abstract float get(String name, float val) abstract long get(String name, long val)