如下的内容内容是关于java从数据库映射实体类的内容。
package com.share.barter.tool;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.Date;
public class GenEntity {
private static final String NAME = "root";
private static final String PASS = "root";
private static final String DRIVER ="com.mysql.jdbc.Driver";
public GenEntity(){
Connection con;
PreparedStatement pStemt = null;
try {
try {
Class.forName(DRIVER);
} catch (ClassNotFoundException e1) {
e1.printStackTrace();
}
con = DriverManager.getConnection(URL,NAME,PASS);
pStemt = con.prepareStatement(sql);
ResultSetMetaData rsmd = pStemt.getMetaData();
colnames = new String[size];
colTypes = new String[size];
colSizes = new int[size];
for (int i = 0; i < size; i++) {
colnames[i] = rsmd.getColumnName(i + 1);
colTypes[i] = rsmd.getColumnTypeName(i + 1);
if(colTypes[i].equalsIgnoreCase("datetime")){
f_util = true;
}
if(colTypes[i].equalsIgnoreCase("image") || colTypes[i].equalsIgnoreCase("text")){
f_sql = true;
}
colSizes[i] = rsmd.getColumnDisplaySize(i + 1);
}
String content = parse(colnames,colTypes,colSizes);
try {
File directory = new File("");
String path=this.getClass().getResource("").getPath();
System.out.println(path);
System.out.println("src/?/"+path.substring(path.lastIndexOf("/com/", path.length())) );
FileWriter fw = new FileWriter(directory.getAbsolutePath()+ "/src/"+path.substring(path.lastIndexOf("/com/", path.length()), path.length()) + initcap(tablename) + ".java");
PrintWriter pw = new PrintWriter(fw);
pw.println(content);
pw.flush();
pw.close();
} catch (IOException e) {
e.printStackTrace();
}
} catch (SQLException e) {
e.printStackTrace();
} finally{
}
}
private String parse(String[] colnames, String[] colTypes, int[] colSizes) {
StringBuffer sb = new StringBuffer();
if(f_util){
sb.append("import java.util.Date;rn");
}
if(f_sql){
}
sb.append("package com.share.barter.tool;rn");
sb.append("rn");
sb.append("rnrnpublic class " + initcap(tablename) + "{rn");
sb.append("}rn");
return sb.toString();
}
private void processAllAttrs(StringBuffer sb) {
for (int i = 0; i < colnames.length; i++) {
sb.append("tprivate " + sqlType2JavaType(colTypes[i]) + " " + colnames[i] + ";rn");
}
}
private void processAllMethod(StringBuffer sb) {
for (int i = 0; i < colnames.length; i++) {
sb.append("tpublic void set" + initcap(colnames[i]) + "(" + sqlType2JavaType(colTypes[i]) + " " +
colnames[i] + "){rn");
sb.append("tthis." + colnames[i] + "=" + colnames[i] + ";rn");
sb.append("t}rn");
sb.append("tpublic " + sqlType2JavaType(colTypes[i]) + " get" + initcap(colnames[i]) + "(){rn");
sb.append("ttreturn " + colnames[i] + ";rn");
sb.append("t}rn");
}
}
private String initcap(String str) {
char[] ch = str.toCharArray();
if(ch[0] >= 'a' && ch[0] <= 'z'){
ch[0] = (char)(ch[0] - 32);
}
return new String(ch);
}
private String sqlType2JavaType(String sqlType) {
if(sqlType.equalsIgnoreCase("bit")){
return "boolean";
}else if(sqlType.equalsIgnoreCase("tinyint")){
return "byte";
}else if(sqlType.equalsIgnoreCase("smallint")){
return "short";
}else if(sqlType.equalsIgnoreCase("int")){
return "int";
}else if(sqlType.equalsIgnoreCase("bigint")){
return "long";
}else if(sqlType.equalsIgnoreCase("float")){
return "float";
}else if(sqlType.equalsIgnoreCase("decimal") || sqlType.equalsIgnoreCase("numeric")
|| sqlType.equalsIgnoreCase("real") || sqlType.equalsIgnoreCase("money")
|| sqlType.equalsIgnoreCase("smallmoney")){
return "double";
}else if(sqlType.equalsIgnoreCase("varchar") || sqlType.equalsIgnoreCase("char")
|| sqlType.equalsIgnoreCase("nvarchar") || sqlType.equalsIgnoreCase("nchar")
|| sqlType.equalsIgnoreCase("text")){
return "String";
}else if(sqlType.equalsIgnoreCase("datetime")){
return "Date";
}else if(sqlType.equalsIgnoreCase("image")){
return "Blod";
}
return null;
}
public static void main(String[] args) {
new GenEntity();
}
}
