如果使用无界类型参数，Java编译器会使用Object替换泛型类型参数，如果使用绑定参数作为方法参数，则使用类型.
示例
package com.it1352; public class GenericsTester { public static void main(String[] args) { Box integerBox = new Box(); Box stringBox = new Box(); integerBox.add(new Integer(10)); stringBox.add(new String("Hello World")); printBox(integerBox); printBox1(stringBox); } private static void printBox(T box) { System.out.println("Integer Value :" + box.get()); } private static void printBox1(T box) { System.out.println("String Value :" + ((Box)box).get()); }}class Box { private T t; public void add(T t) { this.t = t; } public T get() { return t; } } 在这种情况下，java编译器将用Object类替换T，在类型擦除之后，编译器将生成字节码以下代码.
package com.it1352; public class GenericsTester { public static void main(String[] args) { Box integerBox = new Box(); Box stringBox = new Box(); integerBox.add(new Integer(10)); stringBox.add(new String("Hello World")); printBox(integerBox); printBox1(stringBox); } //Bounded Types Erasure private static void printBox(Box box) { System.out.println("Integer Value :" + box.get()); } //Unbounded Types Erasure private static void printBox1(Object box) { System.out.println("String Value :" + ((Box)box).get()); }}class Box { private Object t; public void add(Object t) { this.t = t; } public Object get() { return t; } }在这两种情况下，结果都是相同和减去;
输出
Integer Value :10String Value :Hello World