public String execute()

in jspwiki-main/src/main/java/org/apache/wiki/plugin/InsertPage.java [86:210]
89 lines of code
18 McCabe index (conditional complexity)

    public String execute( final Context context, final Map<String, String> params ) throws PluginException {
        final Engine engine = context.getEngine();

        final StringBuilder res = new StringBuilder();

        final String clazz        = TextUtil.replaceEntities(params.get( PARAM_CLASS ));
        final String includedPage = TextUtil.replaceEntities(params.get( PARAM_PAGENAME ));
        String style              = TextUtil.replaceEntities(params.get( PARAM_STYLE ));
        final boolean showOnce    = "once".equals( params.get( PARAM_SHOW ) );
        final String defaultstr   = params.get( PARAM_DEFAULT );
        final int section         = TextUtil.parseIntParameter(params.get( PARAM_SECTION ), -1 );
        int maxlen                = TextUtil.parseIntParameter(params.get( PARAM_MAXLENGTH ), -1 );

        final ResourceBundle rb = Preferences.getBundle( context, Plugin.CORE_PLUGINS_RESOURCEBUNDLE );

        if( style == null ) {
            style = DEFAULT_STYLE;
        }

        if( maxlen == -1 ) {
            maxlen = Integer.MAX_VALUE;
        }

        if( includedPage != null ) {
            final Page page;
            try {
                final String pageName = engine.getFinalPageName( includedPage );
                page = engine.getManager(PageManager.class).getPage(Objects.requireNonNullElse(pageName, includedPage));
            } catch( final ProviderException e ) {
                res.append( "<span class=\"error\">Page could not be found by the page provider.</span>" );
                return res.toString();
            }

            if( page != null ) {
                //  Check for recursivity
                List<String> previousIncludes = context.getVariable( ATTR_RECURSE );

                if( previousIncludes != null ) {
                    if( previousIncludes.contains( page.getName() ) ) {
                        return "<span class=\"error\">Error: Circular reference - you can't include a page in itself!</span>";
                    }
                } else {
                    previousIncludes = new ArrayList<>();
                }

                // Check for permissions
                final AuthorizationManager mgr = engine.getManager( AuthorizationManager.class );

                if( !mgr.checkPermission( context.getWikiSession(), PermissionFactory.getPagePermission( page, "view") ) ) {
                    res.append("<span class=\"error\">You do not have permission to view this included page.</span>");
                    return res.toString();
                }

                // Show Once
                // Check for page-cookie, only include page if cookie is not yet set
                String cookieName = "";

                if( showOnce ) {
                    cookieName = ONCE_COOKIE + TextUtil.urlEncodeUTF8( page.getName() ).replaceAll( "\\+", "%20" );

                    if( HttpUtil.retrieveCookieValue( context.getHttpRequest(), cookieName ) != null ) {
                        return "";  //silent exit
                    }

                }

                // move here, after premature exit points (permissions, page-cookie)
                previousIncludes.add( page.getName() );
                context.setVariable( ATTR_RECURSE, previousIncludes );

                /**
                 *  We want inclusion to occur within the context of
                 *  its own page, because we need the links to be correct.
                 */

                final Context includedContext = context.clone();
                includedContext.setPage( page );

                String pageData = engine.getManager( PageManager.class ).getPureText( page );
                String moreLink = "";

                if( section != -1 ) {
                    try {
                        pageData = TextUtil.getSection( pageData, section );
                    } catch( final IllegalArgumentException e ) {
                        throw new PluginException( e.getMessage() );
                    }
                }

                if( pageData.length() > maxlen ) {
                    pageData = pageData.substring( 0, maxlen )+" ...";
                    moreLink = "<p><a href=\""+context.getURL( ContextEnum.PAGE_VIEW.getRequestContext(),includedPage)+"\">"+rb.getString("insertpage.more")+"</a></p>";
                }

                res.append("<div class=\"inserted-page ");
                if( clazz != null ) res.append( clazz );
                if( !style.equals(DEFAULT_STYLE) ) res.append( "\" style=\"" ).append( style );
                if( showOnce ) res.append( "\" data-once=\"" ).append( cookieName );
                res.append("\" >");

                res.append( engine.getManager( RenderingManager.class ).textToHTML( includedContext, pageData ) );
                res.append( moreLink );

                res.append("</div>");

                //
                //  Remove the name from the stack; we're now done with this.
                //
                previousIncludes.remove( page.getName() );
                context.setVariable( ATTR_RECURSE, previousIncludes );
            } else {
                if( defaultstr != null ) {
                    res.append( defaultstr );
                } else {
                    res.append( "There is no page called '" ).append( includedPage ).append( "'.  Would you like to " );
                    res.append( "<a href=\"" ).append( context.getURL( ContextEnum.PAGE_EDIT.getRequestContext(), includedPage ) ).append( "\">create it?</a>" );
                }
            }
        } else {
            res.append( "<span class=\"error\">" );
            res.append( "You have to define a page!" );
            res.append( "</span>" );
        }
        return res.toString();
    }