public CCHttpRequest(final String url,
final Map<String, String> params,
final CCApiCallback callback) {
mRequest = new HttpStringRequest(HttpGsonRequest.Method.POST, url) {
@Override
protected Map<String, String> getParams() {
return params;
}
@Override
protected void onResponse(String s) {<pre name="code" class="java"> <span style="white-space:pre"> </span>if (null != callback) {
callback.onResponse(data.toString(), hasServerTime, serverTime);
} } @Override protected void onErrorResponse(Exception e) { if (null != callback) { //系统错误返回-1 callback.onError(createErrorMessage(-1, e.getMessage())); } } }; }
被Volley缓存持有的对象是new HttpStringRequest 这个匿名类对象的实例，为什么方法中的参数final CCApiCallback callback这个参数会被新创建出来的匿名内部内持有呢？public class Hello{
private String mName="37785612";
class Demo{
public void show(){
}
}
public void showDemo(final String s){
new Demo(){
public void show(){
System.out.println("s="+s);
System.out.println("name="+mName);
}
}.show();
}
}执行javac Hello.java编译完成后,会在同一目录下生成如下几个class文件，Hello.class,Hello$1.class,Hello$Demo.class。Hello.class就是我们源文件Hello的类文件，Hello$1.class是在showDemo()方法里面new Demo()那个匿名类的类文件，Hello$Demo.class是内部类Demo的类文件，我们这里主要分析Hello.class与Hello$1.class.{
public Hello();
Code:
Stack=2, Locals=1, Args_size=1
0: aload_0
1: invokespecial #2; //Method java/lang/Object."<init>":()V
4: aload_0
5: ldc #3; //String 37785612
7: putfield #1; //Field mName:Ljava/lang/String;
10: return
LineNumberTable:
line 1: 0
line 2: 4
line 3: 10
public void showDemo(java.lang.String);
Code:
Stack=4, Locals=2, Args_size=2
0: new #4; //class Hello$1
3: dup
4: aload_0
5: aload_1
6: invokespecial #5; //Method Hello$1."<init>":(LHello;Ljava/lang/String;)V
9: invokevirtual #6; //Method Hello$1.show:()V
12: return
LineNumberTable:
line 8: 0
line 14: 12
static java.lang.String access$000(Hello);
Code:
Stack=1, Locals=1, Args_size=1
0: aload_0
1: getfield #1; //Field mName:Ljava/lang/String;
4: areturn
LineNumberTable:
line 1: 0
}
可以看到这里有一个方法access$000(Hello)是我们在源文件中没有出现的，而编译后会多了这个方法，它其实都是返回变量mName的值，后面会说到这个方法会被怎么用{
final java.lang.String val$s;
final Hello this$0;
Hello$1(Hello, java.lang.String);
Code:
Stack=2, Locals=3, Args_size=3
0: aload_0
1: aload_1
2: putfield #1; //Field this$0:LHello;
5: aload_0
6: aload_2
7: putfield #2; //Field val$s:Ljava/lang/String;
10: aload_0
11: aload_1
12: invokespecial #3; //Method Hello$Demo."<init>":(LHello;)V
15: return
LineNumberTable:
line 8: 0
public void show();
Code:
Stack=3, Locals=1, Args_size=1
0: getstatic #4; //Field java/lang/System.out:Ljava/io/PrintStream;
3: new #5; //class java/lang/StringBuilder
6: dup
7: invokespecial #6; //Method java/lang/StringBuilder."<init>":()V
10: ldc #7; //String s=
12: invokevirtual #8; //Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
15: aload_0
16: getfield #2; //Field val$s:Ljava/lang/String;
19: invokevirtual #8; //Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
22: invokevirtual #9; //Method java/lang/StringBuilder.toString:()Ljava/lang/String;
25: invokevirtual #10; //Method java/io/PrintStream.println:(Ljava/lang/String;)V
28: getstatic #4; //Field java/lang/System.out:Ljava/io/PrintStream;
31: new #5; //class java/lang/StringBuilder
34: dup
35: invokespecial #6; //Method java/lang/StringBuilder."<init>":()V
38: ldc #11; //String name=
40: invokevirtual #8; //Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
43: aload_0
44: getfield #1; //Field this$0:LHello;
47: invokestatic #12; //Method Hello.access$000:(LHello;)Ljava/lang/String;
50: invokevirtual #8; //Method java/lang/StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
53: invokevirtual #9; //Method java/lang/StringBuilder.toString:()Ljava/lang/String;
56: invokevirtual #10; //Method java/io/PrintStream.println:(Ljava/lang/String;)V
59: return
LineNumberTable:
line 10: 0
line 11: 28
line 12: 59
}
43: aload_0 44: getfield #1; //Field this$0:LHello; 47: invokestatic #12; //Method Hello.access$000:(LHello;)Ljava/lang/String;43，调用匿名内的this对象，44，取得匿名类的this$0成员变量，就是(Hello对象) 47 调用Hello的静态方法static java.lang.String access$000(Hello);获取成员mName的值
原文地址：http://blog.csdn.net/crabisacoolboy/article/details/45340659
