.class-file

问题 I am using ASM (for the first time) in an application to create Java class files. This is for the backend of a compiler I am writing. I read the relevant parts of the ASM documentation and have a question about stack map frames. ASM says it can automatically compute those frames if the class writer is initialized with the appropriate flags. My question is, does that mean I will not ever have to call the visitLocalVariable() method on the method visitors myself? I am not sure what that method

问题 I'm going to make a simple compiler for a school project, i want generate .class file, i read the file format but to understand better the .class file format and the java bytecode i have this class: public class Me { public void myMethod() { int a = 5 * 4 + 3 - 2 + 1 / 7 + 28; } } with javap command i get this(for 'myMethod'): public void myMethod(); flags: ACC_PUBLIC Code: stack=1, locals=2, args_size=1 0: bipush 49 2: istore_1 3: return LineNumberTable: line 3: 0 line 4: 3

问题 I was looking into how the Java bytecode worked, and I started on Wikipedia. On the page focusing on the .class file, it mentions 11 constant types that appear in the Constant Pool. However, in The Java Virtual Machine Specifications (JVMS) it mentions 3 more: CONSTANT_MethodHandle CONSTANT_MethodType CONSTANT_InvokeDynamic The 11 mentioned on the Wikipedia page seem fairly self-explanatory, and I understand their purpose and use. However, I'm confused by the 3 extra described in the JVMS.

问题 Frankly, I do not know even it is possible or not. But what I am trying to do is just like below. I made a class file from ClassFile.java via javac command in terminal. Then I want to get an instance from .java file or .class file. Next, I made another project in eclipse, As you guess this project path and upper file path are completely different. For instance, ClassFile.java/class file can be located in '~/Downloads' folder, the other hand, new eclipse project can be in '~/workspace/'. So I

问题 I am attempting to use Gradle (for the first time) for a multiproject java build. I have created a settings.gradle file with all the project names. I have also create a very basic build.gradle file. To my surprise when I run gradle build. It returns BUILD SUCCESSFUL. Jars are created in the build\libs folder. What is puzzling to me is that no .class files exists. Also I have been unable to get any kind of Junit results or xml output. I'm wondering if this is really building correctly. For now

问题 Is there any tool that can remove debug info from Java .class files, just like /usr/bin/strip can from C/C++ object files on Linux? EDIT: I liked both Thilo's and Peter Mmm's answers: Peter's was short and to the point exposing my ignorance of what ships with JDK; Thilo's ProGuard suggestion is something I'll definitely be checking out anyway for all those extra features it appears to provide. Thank you Thilo and Peter! 回答1: ProGuard (which the Android SDK for example ships with to reduce

问题 I would like to write a compiler for a toy-language for Java. I would like to generate runnable .class files. I was wondering what is the best library or tool available for doing this? I know I could learn the binary format for all the instructions and build my own constant pool etc, but that seems like work that ought to have been already done: no point reinventing the wheel, right? Searching online I've found two different Java Assembly languages, Jasmin and Jamaica, however only Jasmin

问题 I would like to write a compiler for a toy-language for Java. I would like to generate runnable .class files. I was wondering what is the best library or tool available for doing this? I know I could learn the binary format for all the instructions and build my own constant pool etc, but that seems like work that ought to have been already done: no point reinventing the wheel, right? Searching online I've found two different Java Assembly languages, Jasmin and Jamaica, however only Jasmin

问题 i have one enum as enum OperationsType { ADD("+"), SUB("-"), DIV("/"), MUL("*"); private String opcodes; private OperationsType(String opcodes) { this.opcodes = opcodes; } public String toString() { return this.opcodes; } } Here all enum type doesn't have any constant Specific method so javac is creating only one class file for enum as OperationsType.class but if i add constant Specific method in same code for all enum type then javac is creating 5 class files. Operations.class Operations$1

问题 Inside a jsp I have a small header : <%@ page import="java.util.*"%> <% HttpSession CurrentSession = request.getSession(); ... %> ...and a big html <html> ... </html> If I try to read it as is I get an error of "...is exceeding the 65535 bytes limit".I have to break it up.Since I am new to java I cannot figure it out how to do it.Could you please indicate me the way? 回答1: The JSP is converted into a normal Servlet java source, and some generated method is too large, as there is a 64 KB limit