我的代码是空指针异常
J2MESDLIB.generateDB(true);
J2MEColumn c1 = new J2MEColumn("desc", true, J2MEColumn.ColumnType.VARCHAR, 20);
J2MEColumn c2=new J2MEColumn("date", false, J2MEColumn.ColumnType.VARCHAR, 20);
J2MEColumn c3=new J2MEColumn("type", false, J2MEColumn.ColumnType.VARCHAR, 20);
J2MEColumn c4=new J2MEColumn("assigned", false, J2MEColumn.ColumnType.VARCHAR, 100);
Vector vector=new Vector(4);
vector.addElement(c1);
vector.addElement(c2);
vector.addElement(c3);
vector.addElement(c4);
J2METable table1=J2MESDLIB.createTable("todo", vector, 1);
它给人的异常在最后一行 即显示java.lang.NullPointerException 显示java.lang.NullPointerException 在edu.upc.J2MESDLIB.J2MEDBException。( J2MEDBException.java:82) 在edu.upc.J2MESDLIB.J2MESDLIB.createTable(J2MESDLIB.java:193) 在hello.TodoRecordStore.openRecord(TodoRecordStore.java:52)