Add LOG_TO_CONSOLE property to enable/disable console logging

Author: skybber

hotswap-agent-core/src/main/java/org/hotswap/agent/config/LogConfigurationHelper.java

@@ -39,6 +39,7 @@ public class LogConfigurationHelper {
     public static final String DATETIME_FORMAT = "LOGGER_DATETIME_FORMAT";
     private static final String LOGFILE = "LOGFILE";
     private static final String LOGFILE_APPEND = "LOGFILE.append";
+    private static final String LOG_TO_CONSOLE = "LOG_TO_CONSOLE";
 
     /**
      * Search properties for prefix LOGGER and set level for package in format:
@@ -75,6 +76,8 @@ public static void configureLog(Properties properties) {
                     LOGGER.error("Invalid configuration property {} value '{}'. Unable to create/open the file.",
                             e, LOGFILE, logfile);
                 }
+            } else if (property.equals(LOG_TO_CONSOLE)) {
+                AgentLogger.getHandler().setLogToConsole(parseBoolean(properties.getProperty(LOG_TO_CONSOLE, "true")));
             }
         }
     }

hotswap-agent-core/src/main/java/org/hotswap/agent/logging/AgentLoggerHandler.java

@@ -33,6 +33,7 @@ public class AgentLoggerHandler {
 
     // stream to receive the log
     PrintStream outputStream;
+    private boolean logToConsole = true;
 
     SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss.SSS");
 
@@ -45,10 +46,20 @@ public void setPrintStream(PrintStream outputStream) {
         this.outputStream = outputStream;
     }
 
+    public void setLogToConsole(boolean logToConsole) {
+        this.logToConsole = logToConsole;
+    }
+
+    public boolean isLogToConsole() {
+        return logToConsole;
+    }
+
     // print a message to System.out and optionally to custom stream
     protected void printMessage(String message) {
         String log = "HOTSWAP AGENT: " + sdf.format(new Date()) +  " " + message;
-        System.out.println(log);
+        if (logToConsole) {
+            System.out.println(log);
+        }
         if (outputStream != null)
             outputStream.println(log);
     }

hotswap-agent-core/src/main/resources/hotswap-agent.properties

@@ -80,6 +80,8 @@ LOGGER=info
 # Print output into logfile (with choice to append - false by default)
 # LOGFILE=agent.log
 # LOGFILE.append=true
+# Print output to the console (true by default)
+# LOG_TO_CONSOLE=true
 
 # Comma separated list of class loaders to exclude from initialization, in the form of RegEx patterns.
 #excludedClassLoaderPatterns=jdk.nashorn.*