我正在尝试读取文本文件并在 SQL SERVER 数据库中创建表，但是在执行此操作时出现错误 null，所以我应该使用不同类型的 SQL 语句来执行吗？或者是Resultset和dmd.geTables的问题，对此给出一些想法和建议。
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我的文本文件：
COLUMN_NAME COLUMN_TYPE IS_NULLABLE COLUMN_KEY COLUMN_DEFAULT EXTRA
FirstName VARCHAR(20) NO
LastName VARCHAR(20) NO
Gender VARCHAR(20) NO
Address VARCHAR(20) NO
PhoneNo VARCHAR(50) NO
Email VARCHAR(50) NO
DOB VARCHAR(20) NO
Occupation VARCHAR(50) NO
Password VARCHAR(30) YES
到目前为止的代码：
import java.io.*;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.util.*;
import javax.swing.*;
import javax.swing.table.*;
public class Stackq extends AbstractTableModel {
Vector<String> data;
Vector columns;
public Stackq() {
String line;
data = new Vector<String>();
columns = new Vector();
int count = 0;
try {
FileInputStream fis = new FileInputStream("V:/Jimmy/text/registration.txt");
BufferedReader br = new BufferedReader(new InputStreamReader(fis));
StringTokenizer st1 = new StringTokenizer(br.readLine(), "\t");
while (st1.hasMoreTokens()) {
columns.addElement(st1.nextToken());
count++;
}
while ((line = br.readLine()) != null) {
StringTokenizer st2 = new StringTokenizer(line, "\t");
for (int i = 0; i < count; i++) {
if (st2.hasMoreTokens()) {
data.addElement(st2.nextToken());
} else {
data.addElement("");
}
}
}
br.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public void setValueAt(Object value, int row, int col) {
data.setElementAt((String) value, col);
fireTableCellUpdated(row, col);
}
public boolean isCellEditable(int row, int col) {
//if (4 == col){
return true;
}
//else {
// return false;
// }
//}
//public void insertData(Object[] values){
// data.add(new Vector());
//for(int i =0; i<values.length; i++){
//((Vector) data.get(data.size()-1)).add(values[i]);
//}
//fireTableDataChanged();
// }
public void removeRow(int row) {
data.removeElementAt(row);
fireTableDataChanged();
}
public int getRowCount() {
return data.size() / getColumnCount();
}
public int getColumnCount() {
return columns.size();
}
public Object getValueAt(int rowIndex, int columnIndex) {
return (String) data.elementAt((rowIndex * getColumnCount())
+ columnIndex);
}
public String getColumnName(int i) {
return (String) columns.get(i);
}
public static void main(String args[]) {
Stackq model = new Stackq();
JTable table = new JTable();
table.setModel(model);
JScrollPane scrollpane = new JScrollPane(table);
JPanel panel = new JPanel();
panel.add(scrollpane);
JFrame frame = new JFrame();
frame.add(panel, "Center");
frame.pack();
frame.setVisible(true);
StringBuffer sbTableData = new StringBuffer();
for (int row = 0; row < table.getRowCount(); row++) {
for (int column = 0; column < table.getColumnCount(); column++) {
sbTableData.append(table.getValueAt(row, column)).append("\t");
}
sbTableData.append("\n");
}
System.out.println(sbTableData);
try {
PrintWriter f = new PrintWriter(new BufferedWriter(new FileWriter("V:/Jimmy /text/registration6.txt", true)));
f.println(sbTableData+"\t");
f.close();
} catch (IOException e) {
e.printStackTrace();
}
String readstr1 = null;
int row = table.getRowCount();
int column = table.getColumnCount();
for (int j = 0; j < row; j++) {
for (int i = 0; i < column; i++) {
//System.out.println(table.getValueAt(j, i));
readstr1 = (String) table.getValueAt(j, i);
//System.out.println(readstr);
}
}
try
{
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
java.sql.Connection conn = DriverManager.getConnection("jdbc:sqlserver://localhost\\sqlexpress;databaseName=EMPLOYEE;integratedSecurity=true;");
FileInputStream fstr = new FileInputStream("V:/Jimmy/text/registration6.txt");
// Get the object of DataInputStream
DataInputStream inn = new DataInputStream(fstr);
BufferedReader brr = new BufferedReader(new InputStreamReader(inn));
String readstr;
java.sql.DatabaseMetaData dmd = conn.getMetaData();
ResultSet rs = dmd.getTables(null,"EMPLOYEE","examplea",null);
while ((readstr = brr.readLine()) != null)
//DatabaseMetaData dmd = (DatabaseMetaData) conn.getMetaData();
//while(readstr!=null)
{
//ResultSet rs = dmd.getTables(null, "EMPLOYEE", "example11199", null);
//set not null column
if (String.valueOf(readstr).contains("NO")) {
readstr = readstr.replaceAll("NO", "not null");
} else if (String.valueOf(readstr).contains("YES")) {
readstr = readstr.replaceAll("YES", "");
}
if (String.valueOf(readstr).contains("PRIMARY")) {
readstr = readstr.replaceFirst("PRIMARY", "primary key");
}
System.out.println("replace string " + readstr);
}
try
{
// FILE READ AND TABLE CREATE
String tname = "examplea";
String dbname = "migrationdb";
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
java.sql.Connection conn1 = DriverManager.getConnection("jdbc:sqlserver://localhost\\sqlexpress;databaseName=EMPLOYEE;integratedSecurity=true;");
java.sql.Statement stmt = conn1.createStatement();
// stmt=conn.createStatement();
//System.out.println(readstr1);
try
{
System.out.println("Table creation in process");
if (!rs.next())
{
stmt.executeUpdate("CREATE TABLE " + tname + "("+readstr+")");
System.out.println("connect");
} else {
//System.out.println(readstr);
stmt.executeUpdate("ALTER TABLE " + tname + " ADD("+readstr+")");
System.out.println("altered");
}
brr.close();
conn.close();
conn1.close();
stmt.close();
rs.close();
} catch (Exception e) {
System.out.println(""+e); //Error Statement is Printed Here
}
} catch (Exception e) {
System.out.println(e);
}
} catch (Exception e) {
System.out.println(e);
}
}
}