我想重新打包apache的httpclient lib,用一个Android应用程序发送它(比如https://code.google.com/p/httpclientandroidlib/但是使用HttpClient 4.3.1)
因此,我手动downloaded httpclient 4.3.1 jar(包括其所有依赖项)并使用jarjar重新打包它:
x@x$: cd libs && for f in *.jar; do java -jar ../jarjar-1.4.jar process ../rules.txt $f out/my-$f; done
使用 rules.txt :
rule org.apache.http.** my.repackaged.org.apache.http.@1
然后我用ant将输出放在一起:
<project name="MyProject" default="merge" basedir=".">
<target name="merge">
<zip destfile="my-org-apache-httpclient-4.3.1.jar">
<zipgroupfileset dir="libs/out" includes="*.jar"/>
</zip>
</target>
</project>
我可以使用该文件来开发和测试我的应用程序,但是如果我在android上部署它,它会抛出一个异常,就像找不到my.repackaged.org.apache.logging.log4j.something
引用的my.package.org.apache.logging.whatEver
一样。
所以,现在我想通过使用字节码操作来消除对commons-logging的任何依赖。这已经在以前完成:http://sixlegs.com/blog/java/dependency-killer.html
但我想知道我是怎么做到的? org.apache.commons.logging.Log只有依赖项:
x$x$: java -jar jarjar-1.4.jar find jar my-org-apache-httpclient-4.3.1.jar commons-logging-1.1.3.jar
my/http/impl/execchain/ServiceUnavailableRetryExec -> org/apache/commons/logging/Log
my/http/impl/execchain/RetryExec -> org/apache/commons/logging/Log
my/http/impl/execchain/RedirectExec -> org/apache/commons/logging/Log
my/http/impl/execchain/ProtocolExec -> org/apache/commons/logging/Log
...
我认为要走的路是,删除这些依赖项并将其替换为自己的实现,就像他在这里https://code.google.com/p/httpclientandroidlib/所做的那样。因此,我创建了一个新的maven项目,只有一个具有provided
范围的类,用于实现org.apache.commons.logging.Log接口的commons-logging,只删除android.utils.Log
:
MyLog implements org.apache.commons.logging.Log {}
my.log
中的,我将其打包在my-log-1.0.0.jar中。我将该jar放入与重新打包的httpclient-jars相同的文件夹中,并使用上面提到的ant将所有内容打包在my-org-apache-httpclient-4.3.1.jar中。
方法1
我试图再次使用jarjar:
java -jar jarjar-1.4.jar process rules2.txt my-org-apache-httpclient-4.3.1.jar my-org-apache-httpclient-4.3.1-without-logging-dep.jar
rules2.txt :
rule my.repackaged.commons.logging.** my.log.@1
但这不起作用。 1}}引用my.repackaged.org.apache.logging.log4j.something
无法找到的例外情况仍然存在。
方法2
我还尝试从最终jar中删除日志记录内容和/或重新打包my.repackaged.org.apache.log4j并记录到其原始包:
rules2.txt v2 :
my.package.org.apache.logging.whatEver
但这仍然引起了rule my.repackaged.org.apache.log4j.** org.apache.log4j.@1
rule my.repackaged.org.apache.logging.** org.apache.logging.@1
引用的my.repackaged.org.apache.logging.log4j.something
问题
如何杀死/替换commons-logging依赖项并摆脱异常?
答案 0 :(得分:5)
如果程序依赖于库,通常意味着它使用库的方法。因此,删除依赖关系不是一项简单的任务。您实际上想要删除程序所需的代码 - 至少是正式的。
有三种方法可以删除依赖项:
这些方式都不是很漂亮。所有这些都需要大量的工作。没有保证没有副作用。
我将通过介绍用于解决问题的文件和步骤来描述我的解决方案。要重现,您将需要以下文件(在单个目录中):
lib / xxx-vvvjar :库jars( httpclient 和依赖项,不包括 commons-logging-1.1.3.jar)
jarjar-1.4.jar :用于重新包装罐子
rules.txt :jarjar规则
rule org.apache.http.** my.http.@1
rule org.apache.commons.logging.** my.logging.@1
build.xml :Ant构建配置
<project name="MyProject" basedir=".">
<target name="logimpl">
<javac srcdir="java/src" destdir="java/bin" target="1.5" />
<jar jarfile="out/logimpl.jar" basedir="java/bin" />
</target>
<target name="merge">
<zip destfile="httpclient-4.3.1.jar">
<zipgroupfileset dir="out" includes="*.jar"/>
</zip>
</target>
</project>
<强>的java / SRC / Log.java 强>
package my.logging;
public interface Log {
public boolean isDebugEnabled();
public void debug(Object message);
public void debug(Object message, Throwable t);
public boolean isInfoEnabled();
public void info(Object message);
public void info(Object message, Throwable t);
public boolean isWarnEnabled();
public void warn(Object message);
public void warn(Object message, Throwable t);
public boolean isErrorEnabled();
public void error(Object message);
public void error(Object message, Throwable t);
public boolean isFatalEnabled();
public void fatal(Object message);
public void fatal(Object message, Throwable t);
}
<强>的java / SRC / LogFactory.java 强>
package my.logging;
public class LogFactory {
private static Log log;
public static Log getLog(Class<?> clazz) {
return getLog(clazz.getName());
}
public static Log getLog(String name) {
if(log == null) {
log = new Log() {
public boolean isWarnEnabled() { return false; }
public boolean isInfoEnabled() { return false; }
public boolean isFatalEnabled() { return false; }
public boolean isErrorEnabled() {return false; }
public boolean isDebugEnabled() { return false; }
public void warn(Object message, Throwable t) {}
public void warn(Object message) {}
public void info(Object message, Throwable t) {}
public void info(Object message) {}
public void fatal(Object message, Throwable t) {}
public void fatal(Object message) {}
public void error(Object message, Throwable t) {}
public void error(Object message) {}
public void debug(Object message, Throwable t) {}
public void debug(Object message) {}
};
}
return log;
}
}
<强> do_everything.sh 强>
#!/bin/sh
# Repackage library
mkdir -p out
for jf in lib/*.jar; do
java -jar jarjar-1.4.jar process rules.txt $jf `echo $jf | sed 's/lib\//out\//'`
done
# Compile logging implementation
mkdir -p java/bin
ant logimpl
# Merge jar files
ant merge
那就是它。打开一个控制台并执行
cd my_directory && ./do_everything.sh
这将创建一个文件夹&#34; out&#34;包含单个jar文件和&#34; httpclient-4.3.1.jar&#34;这是最终的,独立的和工作的jar文件。那么,我们刚刚做了什么?
my.http
)my.logging
代替org.apache.commons.logging
my.logging.Log
和my.logging.LogFactory
)要编译的必需类。很简单,不是吗?只需逐行阅读shell脚本即可发现单个步骤。要检查是否已删除所有依赖项,您可以运行
java -jar jarjar-1.4.jar find class httpclient-4.3.1.jar commons-logging-1.1.3.jar
我尝试使用SE7和Android 4.4生成的jar文件,它在两种情况下均有效(请参阅下面的备注)。
每个类文件都有主要版本和次要版本(两者都取决于编译器)。 Android SDK要求类文件的主要版本小于0x33(所以1.7 / JDK 7之前的所有版本)。我将target="1.5"
属性添加到了ant javac
任务中,因此生成的类文件的主要版本为0x31,因此可以包含在您的Android应用中。
你很幸运。记录(几乎总是)是单向操作。它几乎不会引起影响主程序的副作用。这意味着删除 commons-logging 应该是可能的,因为它不会影响程序的功能。
我选择了你在问题中建议的第二种方式字节码操作。这个概念基本上就是这个(A是 httpclient ,B是 commons-logging ):
java.lang.Object
。java.lang.Object
。pop
和常量指令以修复VM堆栈。java.lang.Object
。pop
和常量指令以修复VM堆栈。java.lang.Object
。这需要处理目标类(包含访问字段的类)。java.lang.Object
。正如您所看到的,这背后的想法是用java.lang.Object
替换所有引用的类,并删除对属于 commons-logging 的类成员的所有访问。
我不知道这是否可靠,并且在应用操纵器后我没有测试库。但是从我看到的内容(反汇编的类文件,加载类文件时没有VM错误)我相当肯定代码可以工作。
我试图记录程序的几乎所有内容。它使用ASM Tree API,它提供了对类文件结构的相当简单的访问。并且 - 为了避免不必要的负面评论 - 这是&#34;快速&#39; n&#39;脏&#34;码。我没有真正测试它,我打赌有更快的字节码操作方式。但是这个程序似乎满足了OP的需求以及我所写的所有内容。
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.List;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.jar.JarOutputStream;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.tree.AbstractInsnNode;
import org.objectweb.asm.tree.ClassNode;
import org.objectweb.asm.tree.FieldInsnNode;
import org.objectweb.asm.tree.FieldNode;
import org.objectweb.asm.tree.InsnList;
import org.objectweb.asm.tree.InsnNode;
import org.objectweb.asm.tree.MethodInsnNode;
import org.objectweb.asm.tree.MethodNode;
public class DependencyFinder {
public static void main(String[] args) throws IOException {
if(args.length < 2) return;
DependencyFinder df = new DependencyFinder();
df.analyze(new File(args[0]), new File(args[1]), "org.apache.http/.*", "org.apache.commons.logging..*");
}
@SuppressWarnings("unchecked")
public void analyze(File inputFile, File outputFile, String sClassRegex, String dpClassRegex) throws IOException {
JarFile inJar = new JarFile(inputFile);
JarOutputStream outJar = new JarOutputStream(new FileOutputStream(outputFile));
for(Enumeration<JarEntry> entries = inJar.entries(); entries.hasMoreElements();) {
JarEntry inEntry = entries.nextElement();
InputStream inStream = inJar.getInputStream(inEntry);
JarEntry outEntry = new JarEntry(inEntry.getName());
outEntry.setTime(inEntry.getTime());
outJar.putNextEntry(outEntry);
OutputStream outStream = outJar;
// Only process class files, copy all other resources
if(inEntry.getName().endsWith(".class")) {
// Initialize class reader and writer
ClassReader classReader = new ClassReader(inStream);
ClassWriter classWriter = new ClassWriter(0);
String className = classReader.getClassName();
// Check whether to process this class
if(className.matches(sClassRegex)) {
System.out.println("Processing " + className);
// Parse entire class
ClassNode classNode = new ClassNode(Opcodes.ASM4);
classReader.accept(classNode, 0);
// Check super class and interfaces
String superClassName = classNode.superName;
if(superClassName.matches(dpClassRegex)) {
throw new RuntimeException(className + " extends " + superClassName);
}
for(String iface : (List<String>) classNode.interfaces) {
if(iface.matches(dpClassRegex)) {
throw new RuntimeException(className + " implements " + superClassName);
}
}
// Process methods
for(MethodNode method : (List<MethodNode>) classNode.methods) {
Type methodDesc = Type.getMethodType(method.desc);
boolean changed = false;
// Change return type if necessary
Type retType = methodDesc.getReturnType();
if(retType.getClassName().matches(dpClassRegex)) {
retType = Type.getObjectType("java/lang/Object");
changed = true;
}
// Change argument types if necessary
Type[] argTypes = methodDesc.getArgumentTypes();
for(int i = 0; i < argTypes.length; i++) {
if(argTypes[i].getClassName().matches(dpClassRegex)) {
argTypes[i] = Type.getObjectType("java/lang/Object");
changed = true;
}
}
if(changed) {
// Update method descriptor
System.out.print("Changing " + method.name + methodDesc);
methodDesc = Type.getMethodType(retType, argTypes);
method.desc = methodDesc.getDescriptor();
System.out.println(" to " + methodDesc);
}
// Remove method invocations
InsnList insns = method.instructions;
for(int i = 0; i < insns.size(); i++) {
AbstractInsnNode insn = insns.get(i);
// Ignore all other nodes
if(insn instanceof MethodInsnNode) {
MethodInsnNode mnode = (MethodInsnNode) insn;
Type[] cArgTypes = Type.getArgumentTypes(mnode.desc);
Type cRetType = Type.getReturnType(mnode.desc);
if(mnode.owner.matches(dpClassRegex)) {
// The method belongs to one of the classes we want to get rid of
System.out.println("Removing method call " + mnode.owner + "." +
mnode.name + " in " + method.name);
boolean isStatic = (mnode.getOpcode() == Opcodes.INVOKESTATIC);
if(!isStatic) {
// pop instance
insns.insertBefore(insn, new InsnNode(Opcodes.POP));
}
for(int j = 0; j < cArgTypes.length; j++) {
// pop argument on stack
insns.insertBefore(insn, new InsnNode(Opcodes.POP));
}
// Insert a constant value to repair the stack
if(cRetType.getSort() != Type.VOID) {
InsnNode valueInsn = getValueInstruction(cRetType);
insns.insertBefore(insn, valueInsn);
}
// Remove the actual method call
insns.remove(insn);
// Go back one instruction to not skip the next one
i--;
} else {
changed = false;
if(cRetType.getClassName().matches(dpClassRegex)) {
// Change return type
cRetType = Type.getObjectType("java/lang/Object");
changed = true;
}
for(int j = 0; j < cArgTypes.length; j++) {
if(cArgTypes[j].getClassName().matches(dpClassRegex)) {
// Change argument type
cArgTypes[j] = Type.getObjectType("java/lang/Object");
changed = true;
}
}
if(changed) {
// Update method invocation
System.out.println("Patching method call " + mnode.owner + "." +
mnode.name + " in " + method.name);
mnode.desc = Type.getMethodDescriptor(cRetType, cArgTypes);
}
}
} else if(insn instanceof FieldInsnNode) {
// Yeah I lied... we must not ignore all other instructions
FieldInsnNode fnode = (FieldInsnNode) insn;
Type fieldType = Type.getType(fnode.desc);
if(fnode.owner.matches(dpClassRegex)) {
System.out.println("Removing field access to " + fnode.owner + "." +
fnode.name + " in " + method.name);
// Patch code
switch(fnode.getOpcode()) {
case Opcodes.PUTFIELD:
case Opcodes.GETFIELD:
// Pop instance
insns.insertBefore(insn, new InsnNode(Opcodes.POP));
if(fnode.getOpcode() == Opcodes.PUTFIELD) break;
case Opcodes.GETSTATIC:
// Repair stack
insns.insertBefore(insn, getValueInstruction(fieldType));
break;
default:
throw new RuntimeException("Invalid opcode");
}
// Remove instruction
insns.remove(fnode);
i--;
} else {
if(fieldType.getClassName().matches(dpClassRegex)) {
// Change field type
System.out.println("Patching field access to " + fnode.owner +
"." + fnode.name + " in " + method.name);
fieldType = Type.getObjectType("java/lang/Object");
}
// Update field type
fnode.desc = fieldType.getDescriptor();
}
}
}
}
// Process fields
for(FieldNode field : (List<FieldNode>) classNode.fields) {
Type fieldType = Type.getType(field.desc);
if(fieldType.getClassName().matches(dpClassRegex)) {
System.out.print("Changing " + fieldType.getClassName() + " " + field.name);
fieldType = Type.getObjectType("java/lang/Object");
field.desc = fieldType.getDescriptor();
System.out.println(" to " + fieldType.getClassName());
}
}
// Class processed
classNode.accept(classWriter);
} else {
// Nothing changed
classReader.accept(classWriter, 0);
}
// Write class to JAR entry
byte[] bClass = classWriter.toByteArray();
outStream.write(bClass);
} else {
// Copy file
byte[] buffer = new byte[1024 * 64];
int read;
while((read = inStream.read(buffer)) != -1) {
outStream.write(buffer, 0, read);
}
}
outJar.closeEntry();
}
outJar.flush();
outJar.close();
inJar.close();
}
InsnNode getValueInstruction(Type type) {
switch(type.getSort()) {
case Type.INT:
case Type.BOOLEAN:
return new InsnNode(Opcodes.ICONST_0);
case Type.LONG:
return new InsnNode(Opcodes.LCONST_0);
case Type.OBJECT:
case Type.ARRAY:
return new InsnNode(Opcodes.ACONST_NULL);
default:
// I am lazy, I did not implement all types
throw new RuntimeException("Type not implemented: " + type);
}
}
}