如果JVM本身的版本号 < class文件的版本号,JVM会认为加载不了这个class文件,会抛出我们经常见到的" java.lang.UnsupportedClassVersionError: Bad version number in .classfile " Error 错误;反之,JVM会认为可以加载此class文件,继续加载此class文件。
首先通过premain方法运行JavaAgent,此时在premain参数中我们可以获取到Instrumentation,第二步通过Instrumentation接口将实现的ClassFileTransfomer注册到JVM上,当JVM去加载类的时候,ClassFileTransfomer会获得类的字节数组,并对其进行transform后再返回给JVM,此后该类在Java程序中的表现就是转换之后的结果。 retransform 上述为类...
ACC_SUPERConstant pool:#1=Methodref #22.#42// java/lang/Object."<init>":()V#2=Methodref #43.#44// java/lang/System.currentTimeMillis:()J#3=Class #45// org/objectweb/asm/ClassReader。。。
Normally, the Java virtual machine loads classes from the local file system in a platform-dependent manner. However, some classes may not originate from a file; they may originate from other sources, such as the network, or they could be constructed by an application. The method defineClass ...
Note that the use of unique ids to avoid conflicts is only guaranteed to work reliably when using a local disk file system. Added in 1.4. Java documentation forjava.util.logging.FileHandler. Portions of this page are modifications based on work created and shared by theAndroid Open Source Pro...
Added in 1.7. Java documentation forjava.nio.file.Files. Portions of this page are modifications based on work created and shared by theAndroid Open Source Projectand used according to terms described in theCreative Commons 2.5 Attribution License. ...
To use the AppLogic class, you must first import the com.kivasoft.applogic package at the beginning of your AppLogic file, as shown in the following example: import com.kivasoft.applogic.*; After you import the com.kivasoft.applogic package, you can create an instance of AppLogic and ...
Java documentation forjava.io.FileNotFoundException. Portions of this page are modifications based on work created and shared by theAndroid Open Source Projectand used according to terms described in theCreative Commons 2.5 Attribution License. ...
For writing streams of raw bytes, consider using a FileOutputStream. Added in 1.1. Java documentation for java.io.FileWriter. Portions of this page are modifications based on work created and shared by the Android Open Source Project and used according to terms described in the Creative Commons...
THIS chapter describes the Java virtual machine class file format. Each class file contains the definition of a single class or interface. Although a class or interface need not have an external representation literally contained in a file (for instance, ...