question: gets the value of the extension property . this accessor method returns a reference to the live list , not a snapshot . therefore any modification you make to the returned list will be present inside the jaxb object . this is why there is not a set method for the extension property . for example , to add a new item , do as follows : getextension . add newitem ; objects of the following type s are allowed in the list extensiontype concode_field_sep ExtensionOnlyType mobileNetworkNoEncryption concode_elem_sep ExtensionOnlyType ipSec concode_elem_sep ExtensionOnlyType adsl concode_elem_sep List<ExtensionType> extension concode_elem_sep ExtensionOnlyType wtls concode_elem_sep ExtensionOnlyType isdn concode_elem_sep ExtensionOnlyType http concode_elem_sep ExtensionOnlyType pstn concode_elem_sep ExtensionOnlyType mobileNetworkRadioEncryption concode_elem_sep ExtensionOnlyType mobileNetworkEndToEndEncryption concode_elem_sep ExtensionOnlyType ssl concode_field_sep void setHTTP concode_elem_sep ExtensionOnlyType getHTTP concode_elem_sep ExtensionOnlyType getMobileNetworkRadioEncryption concode_elem_sep void setMobileNetworkRadioEncryption concode_elem_sep void setSSL concode_elem_sep ExtensionOnlyType getISDN concode_elem_sep ExtensionOnlyType getMobileNetworkNoEncryption concode_elem_sep void setMobileNetworkNoEncryption concode_elem_sep ExtensionOnlyType getADSL concode_elem_sep ExtensionOnlyType getMobileNetworkEndToEndEncryption concode_elem_sep ExtensionOnlyType getPSTN concode_elem_sep void setIPSec concode_elem_sep void setPSTN concode_elem_sep void setWTLS concode_elem_sep void setADSL concode_elem_sep void setMobileNetworkEndToEndEncryption concode_elem_sep ExtensionOnlyType getWTLS concode_elem_sep void setISDN concode_elem_sep ExtensionOnlyType getSSL concode_elem_sep ExtensionOnlyType getIPSec
target: List < ExtensionType > function ( ) { if ( extension == null ) { extension = new ArrayList < ExtensionType > ( ) ; } return this . extension ; }