java-bytecode-asm | 易学教程

ArrayOutOfBoundsException: asm.ClassReader.readClass(Unknown Source) [duplicate]

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问题 This question already has answers here : Failed to load ApplicationContext caused by ArrayIndexOutOfBoundsException in ClassReader (5 answers) Closed 2 years ago . I have a hierarchy with the following dependencies: Base(Timer timer) Timer(PublisherService service, BaseDao userDao, DataProcessor processor) There are additional dependencies within DataProcessor but I will not go that far because it seems my error occurs a lot earlier. In correspondence with that dependency graph, I have the

ASM Get exact value from stack frame

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I have some method, which contains instrustion like ILOAD, and I want in some way to get value of stack after this instruction. Not just type, but exact value. I know I need to emulate method execution in order to do that, but I don't know how to make this properly. I have such method for test called main : sipush 15649 istore_0 /* c */ getstatic java/lang/System.out:Ljava/io/PrintStream; bipush 45 bipush 11 iload_0 /* c */ ... I want to get value, loaded by iload_0 . I tried to make Analyzer and then see Frame values, but they only contains type of values, not exact what I want. ClassReader

Java: Getting Bytecode of Class at Runtime from within the Same JVM

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问题 Related to: Is there a way to obtain the bytecode for a class at runtime? I'm adding durability to Clojure, and I'm finally at the point where I'm ready to add functions. In Clojure, functions are byte compiled into classes with invoke methods (among others). In this way, functions are first class. To make these durable, I need to serialize and deserialize these classes. How do I get the bytecode for the class without having access to the .class file? Please correct me if I'm mistaken, but

Java method parameters values in ASM

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问题 I am trying to get the values of a Java program's method's parameters. I am using ASM to instrument the bytecode and getting these values. However, I'm running into some troubles. Here is the visitCode() method used to instrument the code. What it is doing is : Create an empty array to store the collected parameters. For each parameter, load its value into the array. Send this array to my agent's OnMethodEntry method (which where the values will be used). . @Override public void visitCode() {

Understanding javap's output for the Constant Pool

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问题 When running javap on a very simple HelloWorld application I have some confusion on the output around the constant pool. Test Code public class TestClass { public static void main(String[] args) { System.out.println("hello world"); } } Javap -c -verbose output (snipped) // Header + consts 1..22 snipped const #22 = String #23; // hello world const #23 = Asciz hello world; public static void main(java.lang.String[]); Signature: ([Ljava/lang/String;)V Code: Stack=2, Locals=1, Args_size=1 0:

Error : java.lang.NoSuchMethodError: org.objectweb.asm.ClassWriter.<init>(I)V

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I am developing a small Spring application. I have to store the details of the student information in the database. I have developed one SimpleFormController. I have used NetBeans + Hibernate mapping + Spring. When I deploy the project, the following errors occurs. My spring-config-db-applicationContext.xml is shown below: <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd"> <beans>  <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"