protected String accessJMXValue() 
{
        try {
            Object result = getJMXConnection().getAttribute(
                    new ObjectName(name), attribute);
            if(result != null)
                return result.toString();
        } catch (Exception e) {
            // ignore access or connection open errors
        }
        return null;
}

Get value from MBeans attribute

 public boolean eval() 
{
        if (operation == null) {
            throw new BuildException("operation attribute is not set");
        }
        if (value == null) {
            throw new BuildException("value attribute is not set");
        }
        if ((name == null || attribute == null)) {
            throw new BuildException(
                    "Must specify a 'attribute', name for equals condition");
        }
        if (testIfCondition() && testUnlessCondition()) {
            String jmxValue = accessJMXValue();
            if (jmxValue != null) {
                String op = getOperation();
                if ("==".equals(op)) {
                    return jmxValue.equals(value);
                } else if ("!=".equals(op)) {
                    return !jmxValue.equals(value);
                } else {
                    if ("long".equals(type)) {
                        long jvalue = Long.parseLong(jmxValue);
                        long lvalue = Long.parseLong(value);
                        if (" >".equals(op)) {
                            return jvalue  > lvalue;
                        } else if (" >=".equals(op)) {
                            return jvalue  >= lvalue;
                        } else if ("< ".equals(op)) {
                            return jvalue <  lvalue;
                        } else if ("< =".equals(op)) {
                            return jvalue < = lvalue;
                        }
                    } else if ("double".equals(type)) {
                        double jvalue = Double.parseDouble(jmxValue);
                        double dvalue = Double.parseDouble(value);
                        if (" >".equals(op)) {
                            return jvalue  > dvalue;
                        } else if (" >=".equals(op)) {
                            return jvalue  >= dvalue;
                        } else if ("< ".equals(op)) {
                            return jvalue <  dvalue;
                        } else if ("< =".equals(op)) {
                            return jvalue < = dvalue;
                        }
                    }
                }
            }
            return false;
        }
        return true;
}

This method evaluates the condition It support for operation ">,>=,<,<=" the types long and double.

 public String getAttribute() 
{
        return attribute;
}

 public String getHost() 
{
        return host;
}

 public String getIf() 
{
        return ifCondition;
}

 public String getInfo() 
{
                        
        return (info);
}

Return descriptive information about this implementation and the corresponding version number, in the format <description>/<version>.

 protected MBeanServerConnection getJMXConnection() throws MalformedURLException, IOException 
{
        return JMXAccessorTask.accessJMXConnection(
                getProject(),
                getUrl(), getHost(),
                getPort(), getUsername(), getPassword(), ref);
}

Get JMXConnection (default look at jmx.server project reference from jmxOpen Task)

 public String getName() 
{
        return name;
}

 public String getOperation() 
{
        return operation;
}

 public String getPassword() 
{
        return password;
}

 public String getPort() 
{
        return port;
}

 public String getRef() 
{
        return ref;
}

 public String getType() 
{
        return type;
}

 public String getUnless() 
{
        return unlessCondition;
}

 public String getUrl() 
{
        return url;
}

 public String getUsername() 
{
        return username;
}

 public String getValue() 
{
        return value;
}

 public  void setAttribute(String attribute) 
{
        this.attribute = attribute;
}

 public  void setHost(String host) 
{
        this.host = host;
}

 public  void setIf(String c) 
{
        ifCondition = c;
}

Only execute if a property of the given name exists in the current project.

 public  void setName(String objectName) 
{
        this.name = objectName;
}

 public  void setOperation(String operation) 
{
        this.operation = operation;
}

 public  void setPassword(String password) 
{
        this.password = password;
}

 public  void setPort(String port) 
{
        this.port = port;
}

 public  void setRef(String refId) 
{
        this.ref = refId;
}

 public  void setType(String type) 
{
        this.type = type;
}

 public  void setUnless(String c) 
{
        unlessCondition = c;
}

Only execute if a property of the given name does not exist in the current project.

 public  void setUrl(String url) 
{
        this.url = url;
}

 public  void setUsername(String username) 
{
        this.username = username;
}

 public  void setValue(String value) 
{
        this.value = value;
}

 protected boolean testIfCondition() 
{
        if (ifCondition == null || "".equals(ifCondition)) {
            return true;
        }
        return getProject().getProperty(ifCondition) != null;
}

test the if condition

 protected boolean testUnlessCondition() 
{
        if (unlessCondition == null || "".equals(unlessCondition)) {
            return true;
        }
        return getProject().getProperty(unlessCondition) == null;
}

test the unless condition