improve the attach mode

Signed-off-by: pengzhile <pengzhile@gmail.com>

README.md

@@ -1,4 +1,4 @@
-# ja-netfilter v2.2.2
+# ja-netfilter v2.2.3
 
 ### A javaagent framework
 

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>com.ja-netfilter</groupId>
     <artifactId>ja-netfilter</artifactId>
-    <version>2.2.2</version>
+    <version>2.2.3</version>
 
     <name>ja-netfilter</name>
     <description>A javaagent framework</description>

src/main/java/com/janetfilter/core/Dispatcher.java

@@ -9,11 +9,26 @@ import java.security.ProtectionDomain;
 import java.util.*;
 
 public final class Dispatcher implements ClassFileTransformer {
+    private final Environment environment;
     private final Set<String> classSet = new TreeSet<>();
     private final Map<String, List<MyTransformer>> transformerMap = new HashMap<>();
     private final List<MyTransformer> globalTransformers = new ArrayList<>();
 
+    public Dispatcher(Environment environment) {
+        this.environment = environment;
+    }
+
     public synchronized void addTransformer(MyTransformer transformer) {
+        if (environment.isAttachMode() && !transformer.attachMode()) {
+            DebugInfo.debug("Transformer: " + transformer.getClass().getName() + " is set to not load in attach mode, ignored.");
+            return;
+        }
+
+        if (environment.isJavaagentMode() && !transformer.javaagentMode()) {
+            DebugInfo.debug("Transformer: " + transformer.getClass().getName() + " is set to not load in -javaagent mode, ignored.");
+            return;
+        }
+
         String className = transformer.getHookClassName();
         if (null == className) {
             globalTransformers.add(transformer);

src/main/java/com/janetfilter/core/Environment.java

@@ -16,12 +16,13 @@ public final class Environment {
     private final File logsDir;
     private final String nativePrefix;
     private final String disabledPluginSuffix;
+    private final boolean attachMode;
 
-    public Environment(File agentFile) {
-        this(agentFile, null);
+    public Environment(File agentFile, boolean attachMode) {
+        this(agentFile, null, attachMode);
     }
 
-    public Environment(File agentFile, String app) {
+    public Environment(File agentFile, String app, boolean attachMode) {
         this.agentFile = agentFile;
         baseDir = agentFile.getParentFile();
 
@@ -41,6 +42,7 @@ public final class Environment {
         version = Launcher.VERSION;
         nativePrefix = StringUtils.randomMethodName(15) + "_";
         disabledPluginSuffix = ".disabled.jar";
+        this.attachMode = attachMode;
     }
 
     public String getPid() {
@@ -83,6 +85,14 @@ public final class Environment {
         return disabledPluginSuffix;
     }
 
+    public boolean isAttachMode() {
+        return attachMode;
+    }
+
+    public boolean isJavaagentMode() {
+        return !attachMode;
+    }
+
     @Override
     public String toString() {
         return "Environment: {" +
@@ -96,6 +106,7 @@ public final class Environment {
                 ", \n\tlogsDir = " + logsDir +
                 ", \n\tnativePrefix = " + nativePrefix +
                 ", \n\tdisabledPluginSuffix = " + disabledPluginSuffix +
+                ", \n\tattachMode = " + attachMode +
                 "\n}";
     }
 }

src/main/java/com/janetfilter/core/Initializer.java

@@ -11,7 +11,7 @@ public class Initializer {
         DebugInfo.useFile(environment.getLogsDir());
         DebugInfo.info(environment.toString());
 
-        Dispatcher dispatcher = new Dispatcher();
+        Dispatcher dispatcher = new Dispatcher(environment);
         new PluginManager(inst, dispatcher, environment).loadPlugins();
 
         inst.addTransformer(dispatcher, true);

src/main/java/com/janetfilter/core/Launcher.java

@@ -12,7 +12,7 @@ import java.util.jar.JarFile;
 
 public class Launcher {
     public static final String ATTACH_ARG = "--attach";
-    public static final String VERSION = "v2.2.2";
+    public static final String VERSION = "v2.2.3";
 
     private static boolean loaded = false;
 
@@ -42,6 +42,18 @@ public class Launcher {
     }
 
     public static void premain(String args, Instrumentation inst) {
+        premain(args, inst, false);
+    }
+
+    public static void agentmain(String args, Instrumentation inst) {
+        if (null == System.getProperty("janf.debug")) {
+            System.setProperty("janf.debug", "1");
+        }
+
+        premain(args, inst, true);
+    }
+
+    private static void premain(String args, Instrumentation inst, boolean attachMode) {
         if (loaded) {
             DebugInfo.warn("You have multiple `ja-netfilter` as javaagent.");
             return;
@@ -66,11 +78,7 @@ public class Launcher {
             return;
         }
 
-        Initializer.init(inst, new Environment(agentFile, args)); // for some custom UrlLoaders
-    }
-
-    public static void agentmain(String args, Instrumentation inst) {
-        premain(args, inst);
+        Initializer.init(inst, new Environment(agentFile, args, attachMode)); // for some custom UrlLoaders
     }
 
     private static void printUsage() {

src/main/java/com/janetfilter/core/plugin/MyTransformer.java

@@ -6,6 +6,20 @@ public interface MyTransformer {
      */
     String getHookClassName();
 
+    /**
+     * whether to load in attach mode
+     */
+    default boolean attachMode() {
+        return true;
+    }
+
+    /**
+     * whether to load in -javaagent mode
+     */
+    default boolean javaagentMode() {
+        return true;
+    }
+
     /**
      * for global transformers only
      */