三、属性翻译文法
主类声明（MainClass）
<MainClass> ::= "class" <Identifier>↑<id_name1>
@fillMemory↓<id_name1>↑<id_address>
@fillTable↓<id_name1>,<id_address>
@fillTree↓<id_name1>
"{" "public" "static" "void" "main" "(" "String" "[" "]"
<Identifier>↑<id_name2>,<id_belongsTo>=<id_name1>,<id_type>=StringArrayType
@fillTable↓<id_name2>,<id_belongsTo>
"{" <PrintStatement> "}" "}"
类声明（ClassDeclaration）
<ClassDeclaration> ::= "class" <Identifier>↑<id_name>
@checkTable↓<id_name>
@fillMemory↓<id_name1>↑<id_address>
@fillTable↓<id_name>,<id_address>
@fillTree↓<node_name>=<id_name>
"{" ( VarDeclaration )* ( MethodDeclaration )* "}"
类继续声明（ClassExtendsDeclaration）
<ClassExtendsDeclaration> ::= "class" <Identifier>↑<id_name1>
@checkTable↓<id_name1>
"extends" <Identifier>↑<id_name2>
@checkTree↓<id_name2>
@fillMemory↓<id_name1>↑<id_address>
@fillTable↓<id_name1>,<id_name2>,<id_address>
@fillTree↓<child_name>=<id_name1>,<parent_name>=<id_name2>
