diff --git a/src/probes/extends/java.probe/build.sh b/src/probes/extends/java.probe/build.sh
index 4bbc654cdb68d297aaa90ac92f0272c9b169f8ec..f54852aea3816b8813ece1025f7bfdb8d0baf5fc 100755
--- a/src/probes/extends/java.probe/build.sh
+++ b/src/probes/extends/java.probe/build.sh
@@ -4,15 +4,37 @@ PRJ_DIR=$(dirname $(readlink -f "$0"))
 BUILD_FILES=${PRJ_DIR}/jvm.probe
 cd ${BUILD_FILES}
 
-if [ !$JAVA_HOME ];then
-
-	java_link=$(which java)
-	link_path=$(echo $(ls -lrt $java_link) | awk -F " " '{print $NF}' )
-	link_path=$(echo $(ls -lrt $link_path) | awk -F " " '{print $NF}' )
-	jdk_path=$(dirname $(dirname $link_path))
-	javac -cp $jdk_path/lib/tools.jar *.java
+if [ "$1" == "-c"  -o  "$1" == "--clean" ];
+then
+    rm -rf *.class
+    exit
+fi
 
+java_link=$(which java 2>/dev/null)
+javac_link=$(which javac 2>/dev/null)
+	
+if [ -z $java_link ] && [ -z $javac_link ]; 
+then
+    echo "java and javac : command not found"
+    exit 1
 else
-	javac -cp $JAVA_HOME/lib/tools.jar *.java
+    if [ -z $JAVA_HOME ];
+    then
+        # find jdk
+        link_path=$(echo $(ls -lrt $javac_link) | awk -F " " '{print $NF}' )
+        link_path=$(echo $(ls -lrt $link_path) | awk -F " " '{print $NF}' )
+        jdk_path=$(dirname $(dirname $link_path))
+        dir=$jdk_path/lib
+    else
+        dir=$JAVA_HOME/lib
+    fi
 
+    #tools.jar 
+    if [ -e $dir/tools.jar ]; 
+    then
+        javac -cp $dir/tools.jar JvmProbe.java Vm.java
+    else
+        echo "tools.jar not found"
+        exit 1
+    fi 
 fi
diff --git a/src/probes/extends/java.probe/install.sh b/src/probes/extends/java.probe/install.sh
index f125022f0770a431311d81d2676027094276448b..fe0392b26bcc8b2c40e14ac2e02790ff6908e037 100755
--- a/src/probes/extends/java.probe/install.sh
+++ b/src/probes/extends/java.probe/install.sh
@@ -11,6 +11,4 @@ if [ $# -eq 1 ]; then
 		  \cp ${file} $1
        fi
    done
-fi
-
-rm -rf *.class  
+fi