static boolean canFormPalindrome ( String str ) {
  List < Character > list = new ArrayList < Character > ( ) ;
  for ( int i = 0 ;
  i < str . length ( ) ;
  i ++ ) {
    if ( list . contains ( str . charAt ( i ) ) ) list . remove ( ( Character ) str . charAt ( i ) ) ;
    else list . add ( str . charAt ( i ) ) ;
  }
  if ( str . length ( ) % 2 == 0 && list . isEmpty ( ) || ( str . length ( ) % 2 == 1 && list . size ( ) == 1 ) ) return true ;
  else return false ;
}

static boolean canFormPalindrome ( String str ) { List < Character > list = new ArrayList < Character > ( ) ; for ( int i = 0 ; i < str . length ( ) ; i ++ ) { if ( list . contains ( str . charAt ( i ) ) ) list . remove ( ( Character ) str . charAt ( i ) ) ; else list . add ( str . charAt ( i ) ) ; } if ( str . length ( ) % 2 == 0 && list . isEmpty ( ) || ( str . length ( ) % 2 == 1 && list . size ( ) == 1 ) ) return true ; else return false ; }
(method_declaration (modifiers) type: (boolean_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (type_identifier) name: (identifier))) body: (block (local_variable_declaration type: (generic_type (type_identifier) (type_arguments (type_identifier))) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (generic_type (type_identifier) (type_arguments (type_identifier))) arguments: (argument_list)))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))))) consequence: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (cast_expression type: (type_identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))))) alternative: (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))))))) (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (binary_expression left: (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal)) right: (decimal_integer_literal)) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) right: (parenthesized_expression (binary_expression left: (binary_expression left: (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal)) right: (decimal_integer_literal)) right: (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal)))))) consequence: (return_statement (true)) alternative: (return_statement (false)))))