菜鸟上路，多多指教

public static String Procedure_Ins_path(){
    String dir = "e:\\";
    IndexProcesser p;
    p = new IndexProcesser();
    p.searchDirectorys(dir,true);
    String s0 ="DROP SEQUENCE  SEQ_pid;" +
               " CREATE SEQUENCE  SEQ_pid INCREMENT BY 1 START WITH 1 NOCYCLE; ";
    String s1 = "declare " +
               "type path_varray is varray(2000) of varchar2(200); " +
               "p_v path_varray:=path_varray (";
    String s3 =  "); begin " +
                      "for i in 1..2000 loop " +
                         "if p_v(i) = 'null' then " +
                             "p_v(i):='null'; " +
                         "else " +
                             "INSERT INTO tb_allpath (ID ,path) VALUES (SEQ_PID.NEXTVAL,p_v(i));"+
                         "end if; " +
                       "end loop;" +
                    "commit;" +
                    "end;";
    String s2 ="";
           for(int i = 0;i<1999;i++)
               s2 = s2+"'"+p.Directorys[i]+"',";
           s2 = s2 +"'"+ p.Directorys[1999]+"'";
           return s1+s2+s3;
}