java创建实体类(get/set方法链式调用)
1.自动获取数据库表,创建实体类
/**
* 自动获取数据库表,创建实体类
* @since 2020.03.12
* @author qin_myu
*/
public class DomainAutoCreate {
private String tablename = "TABLE_NAME";
// 表名
private String packagename = "com.qmy.domain;
";
// 输出包名
private String classname = "Domain";
// 输出实体类名
private String[] colnames;
// 字段数组
private String[] colTypes;
// 字段类型数组
private int[] colSizes;
// 列名大小数组
private boolean f_util = false;
// 是否需要导入包java.util.*
private boolean f_math = false;
// 是否需要导入包java.math.* public static void main(String[] args) {
new DomainAutoCreate();
} public DomainAutoCreate() {
Connection conn = DBUtil.getConnection();
// 建立数据库连接
PreparedStatement ps = null;
ResultSetMetaData rs = null;
String strsql = "SELECT * FROM " + tablename;
try {
ps = conn.prepareStatement(strsql);
// ResultSet获取结果集
ResultSet rs2 = ps.executeQuery();
// ResultSetMetaData获取表字段及属性
rs = rs2.getMetaData();
int size = rs.getColumnCount();
colnames = new String[size];
colTypes = new String[size];
colSizes = new int[size];
for (int i = 0;
i < rs.getColumnCount();
i++) {
colnames[i] = rs.getColumnName(i + 1).toLowerCase();
colTypes[i] = rs.getColumnTypeName(i + 1).toUpperCase();
if (colTypes[i].equalsIgnoreCase("DATETIME") || colTypes[i].equalsIgnoreCase("DATE")
|| colTypes[i].equalsIgnoreCase("SMALLDATETIME") || colTypes[i].equalsIgnoreCase("TIME")) {
f_util = true;
}
if (colTypes[i].equalsIgnoreCase("MONEY") || colTypes[i].equalsIgnoreCase("DECIMAL")
|| colTypes[i].equalsIgnoreCase("SMALLMONEY") || colTypes[i].equalsIgnoreCase("NUMERIC")) {
f_math = true;
}
colSizes[i] = rs.getColumnDisplaySize(i + 1);
}
String content = parse(colnames, colTypes, colSizes, packagename);
FileWriter fileWriter = new FileWriter(initcap(tablename.toLowerCase()) + ".java");
PrintWriter pw = new PrintWriter(fileWriter);
pw.println(content);
pw.flush();
pw.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
try {
ps.close();
conn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}}
} /**
* 解析处理(生成实体类主体代码)
*
* @param colNames
* @param colTypes
* @param colSizes
* @param packagename
* @return
*/
private String parse(String[] colNames, String[] colTypes, int[] colSizes, String packagename) {
StringBuffer sb = new StringBuffer();
// 导入包
sb.append("package " + packagename + "\r\n\n");
if (f_util) {
sb.append("import java.util.Date;
\r\n\n");
}
if (f_math) {
sb.append("import java.math.BigDecimal;
\r\n\n");
}
sb.append("public class " + initcap(classname) + " {\r\n");
for (int i = 0;
i < colnames.length;
i++) {
sb.append("\tprivate " + sqlTypeToJavaType(colTypes[i]) + " " + colnames[i] + ";
\r\n");
}
sb.append("\n\n");
// 生成get/set方法(链式调用)
for (int i = 0;
i < colnames.length;
i++) {
// get 方法
sb.append("\tpublic " + sqlTypeToJavaType(colTypes[i]) + " get" + initcap(colnames[i]) + "(){\r\n");
sb.append("\t\treturn " + colnames[i] + ";
\r\n");
sb.append("\t}\r\n");
// set 方法
sb.append("\tpublic " + initcap(classname) + " set" + initcap(colnames[i]) + "("
+ sqlTypeToJavaType(colTypes[i]) + " " + colnames[i] + "){\r\n");
sb.append("\t\tthis." + colnames[i] + "=" + colnames[i] + ";
\r\n");
sb.append("\t\treturn this;
\r\n");
sb.append("\t}\r\n");
}
sb.append("}\r\n");
System.out.println(sb.toString());
return sb.toString();
} /**
* 判断数据库字段类型转换为实体类对应函数类型
* @param sqlType
* @return
*/
private String sqlTypeToJavaType(String sqlType) {
if (sqlType.equalsIgnoreCase("BIT")) {
return "Boolean";
} else if (sqlType.equalsIgnoreCase("BINARY") || sqlType.equalsIgnoreCase("IMAGE")
|| sqlType.equalsIgnoreCase("VARBINARY")) {
return "byte[]";
} else if (sqlType.equalsIgnoreCase("SMALLINT") || sqlType.equalsIgnoreCase("TINYINT")) {
return "short";
} else if (sqlType.equalsIgnoreCase("INT") || sqlType.equalsIgnoreCase("INTEGER")) {
return "int";
} else if (sqlType.equalsIgnoreCase("BIGINT")) {
return "long";
} else if (sqlType.equalsIgnoreCase("REAL")) {
return "float";
} else if (sqlType.equalsIgnoreCase("REAL") || sqlType.equalsIgnoreCase("FLOAT")
|| sqlType.equalsIgnoreCase("NUMBER")) {
return "double";
} else if (sqlType.equalsIgnoreCase("DECIMAL") || sqlType.equalsIgnoreCase("SMALLMONEY")
|| sqlType.equalsIgnoreCase("NUMERIC")) {
return "BigDecimal";
} else if (sqlType.equalsIgnoreCase("VARCHAR") || sqlType.equalsIgnoreCase("VARCHAR2")
|| sqlType.equalsIgnoreCase("CHAR") || sqlType.equalsIgnoreCase("NVARCHAR")
|| sqlType.equalsIgnoreCase("NCHAR") || sqlType.equalsIgnoreCase("TEXT")
|| sqlType.equalsIgnoreCase("NTEXT") || sqlType.equalsIgnoreCase("UNIQUEIDENTIFIER")) {
return "String";
} else if (sqlType.equalsIgnoreCase("DATE") || sqlType.equalsIgnoreCase("TIMESTAMP")) {
return "DATE";
// Date
} else if (sqlType.equalsIgnoreCase("SMALLDATETIME") || sqlType.equalsIgnoreCase("DATETIME")) {
return "Timestamp";
} else if (sqlType.equalsIgnoreCase("TIME")) {
return "Time";
}
return null;
} /**
* 把输入字符串的首字母改成大写
* @param str
* @return
*/
private static 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);
}
}
2.java自定义输出实体类
/**
* 自定义字段创建实体类
* @since 2020.03.12
* @author qin_myu
*/
public class DomainCreate { private static String packageName = "com.qmy.domain;
";
// 输出包名
private static String domainPO = "Domain";
// 实体类名
private static String column = "a,b,c,d";
// 字段
private static String columnType = "String,Date,Double,int";
// 字段类型
private static String columnNotes = "a,b,c,d";
// 字段注释
private static String classNotes = "xxxxxxx";
// 类注释
public static void main(String[] args) {
String[] columns = column.split(",");
String[] notes = columnNotes.split(",");
String[] columnTypes = columnType.split(",");
StringBuffer sb = new StringBuffer();
// 包名
sb.append("package " + packageName + "\r\n\n\n");
// 实体类注释
sb.append("/*"+classNotes+"*/\r\n");
sb.append("public class " + domainPO + " {\r\n");
for (int i = 0;
i < columns.length;
i++) {
sb.append("\t// " + notes[i] + "\r\n");
sb.append("\tprivate "+columnTypes[i] +" "+ columns[i] + ";
\r\n");
}sb.append("\n\n");
for (int i = 0;
i < columns.length;
i++) {
// get方法
sb.append("\tpublic "+columnTypes[i] +" get" + initcap(columns[i]) + "(){\r\n");
sb.append("\t\treturn " + columns[i] + ";
\r\n");
sb.append("\t}\r\n");
// set方法(链式调用)
sb.append("\tpublic " + domainPO + " set" + initcap(columns[i]) + "(String " + columns[i] + "){\r\n");
sb.append("\t\tthis." + columns[i] + "=" + columns[i] + ";
\r\n");
sb.append("\t\treturn this;
\r\n");
sb.append("\t}\r\n");
}
sb.append("}\r\n");
System.out.println(sb.toString());
} /**
* 把输入字符串的首字母改成大写
* @param str
* @return
*/
private static 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);
}
}数据库连接工具类
/**
* 建立数据库连接工具类
* @since 2020.03.12
* @author qin_myu
*/
public class DBUtil {
// 驱动,服务器地址,登录用户名,密码
static String DRIVER;
static String DATEBASEURL;
static String USERNAME;
static String PASSWORD;
// Connection连接对象
static Connection conn = null;
// Statement命令对象
static Statement stmt = null;
static PreparedStatement pstmt = null;
static {
/* DB2数据库 */
// DRIVER = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
// DATEBASEURL
// ="jdbc:sqlserver://localhost:1433;
databasename=YerGoMallPro";
// USERNAME = "sa";
// DBPWD = "@zdm168168...";
// PASSWORD = "123456";
// 打开连接/* ORACLE数据库 */
DRIVER = "oracle.jdbc.driver.OracleDriver";
DATEBASEURL = "jdbc:oracle:thin:@localhost:1521/orcl";
USERNAME = "admin";
PASSWORD = "admin";
/* SQLServer数据库 */
// DRIVER= "com.microsoft.sqlserver.jdbc.SQLServerDriver";
// DATEBASEURL= "jdbc:sqlserver://localhost:1433;
DateBaseName=数据库名";
// USERNAME = "sa";
// PASSWORD = "sa";
/* MySQL数据库 */
// DRIVER="com.mysql.jdbc.Driver";
// USERNAME="root";
// PASSWORD="root";
// DATEBASEURL = "jdbc:mysql://localhost/test?user=" + USERNAME +
// "&password=" + PASSWORD+ "&useUnicode=true&characterEncoding=UTF-8";
}
// 通过本方法获得连接对象
public static Connection getConnection() {
try {
if (conn == null || conn.isClosed())
open();
} catch (SQLException e) {
e.printStackTrace();
}
return conn;
}
/**
* 建立连接对象(打开连接)
*/
public static void open() {
try {
// 加载驱动
Class.forName(DRIVER);
conn = DriverManager.getConnection(DATEBASEURL, USERNAME, PASSWORD);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}
/**
* 关闭连接
*/
public static void close() {
try {
if (stmt != null)
stmt.close();
if (conn != null && !conn.isClosed())
conn.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} // executeQuery
// executeUpdate
// execute
// 获得查询的数据集
// select * from student where name='' and sex=''
public static ResultSet executeQuery(String sql) {
try {
open();
// 保证连接是成功的
stmt = conn.createStatement();
return stmt.executeQuery(sql);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
} // 修改表格内容
public static int executeUpdate(String sql) {
int result = 0;
try {
open();
// 保证连接是成功的
stmt = conn.createStatement();
result = stmt.executeUpdate(sql);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
close();
}
return result;
} // 如果执行的查询或存储过程，会返回多个数据集，或多个执行成功记录数
// 可以调用本方法，返回的结果，
// 是一个List或List集合
public static Object execute(String sql) {
boolean b = false;
try {
open();
// 保证连接是成功的
stmt = conn.createStatement();
b = stmt.execute(sql);
// true,执行的是一个查询语句，我们可以得到一个数据集
// false,执行的是一个修改语句，我们可以得到一个执行成功的记录数
if (b) {
return stmt.getResultSet();
} else {
return stmt.getUpdateCount();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
if (!b) {
close();
}
}
return null;
} //
// select * from student where name=? and sex=?
public static ResultSet executeQuery(String sql, Object[] in) {
try {
open();
// 保证连接是成功的
PreparedStatement pst = conn.prepareStatement(sql);
for (int i = 0;
i < in.length;
i++)
pst.setObject(i + 1, in[i]);
stmt = pst;
// 只是为了关闭命令对象pst
return pst.executeQuery();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
} public static int executeUpdate(String sql, Object[] in) {
try {
open();
// 保证连接是成功的
PreparedStatement pst = conn.prepareStatement(sql);
for (int i = 0;
i < in.length;
i++)
pst.setObject(i + 1, in[i]);
stmt = pst;
// 只是为了关闭命令对象pst
return pst.executeUpdate();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
close();
}
return 0;
} public static PreparedStatement pstmt(String sql) {
open();
try {
return pstmt = conn.prepareStatement(sql);
} catch (SQLException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
return null;
} public static Object execute(String sql, Object[] in) {
boolean b = false;
try {
open();
// 保证连接是成功的
PreparedStatement pst = conn.prepareStatement(sql);
for (int i = 0;
i < in.length;
i++)
pst.setObject(i + 1, in[i]);
b = pst.execute();
// true,执行的是一个查询语句，我们可以得到一个数据集
// false,执行的是一个修改语句，我们可以得到一个执行成功的记录数
if (b) {
System.out.println("----");
/*
* List list = new ArrayList();
* list.add(pst.getResultSet());
while(pst.getMoreResults()) {
* list.add(pst.getResultSet());
}
*/
return pst.getResultSet();
} else {
System.out.println("****");
List list = new ArrayList();
list.add(pst.getUpdateCount());
while (pst.getMoreResults()) {
list.add(pst.getUpdateCount());
}
return list;
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {
if (!b) {
System.out.println("====");
close();
}
}
return null;
} // 调用存储过程 proc_Insert(?,?,?)
public static Object executeProcedure(String procName, Object[] in) {
open();
try {
procName = "{call " + procName + "(";
String link = "";
for (int i = 0;
i < in.length;
i++) {
procName += link + "?";
link = ",";
}
procName += ")}";
CallableStatement cstmt = conn.prepareCall(procName);
for (int i = 0;
i < in.length;
i++) {
cstmt.setObject(i + 1, in[i]);
}
if (cstmt.execute()) {
return cstmt.getResultSet();
} else {
return cstmt.getUpdateCount();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}return null;
} /*
* 调用存储过程，并有输出参数
*
* @procName ，存储过程名称：proc_Insert(?,?)
*
* @in ,输入参数集合
*
* @output,输出参数集合
*
* @type,输出参数类型集合
*/
public static Object executeOutputProcedure(String procName, Object[] in, Object[] output, int[] type) {
Object result = null;
try {
CallableStatement cstmt = conn.prepareCall("{call " + procName + "}");
// 设置存储过程的参数值
int i = 0;
for (;
i < in.length;
i++) {// 设置输入参数
cstmt.setObject(i + 1, in[i]);
// print(i+1);
}
int len = output.length + i;
for (;
i < len;
i++) {// 设置输出参数
cstmt.registerOutParameter(i + 1, type[i - in.length]);
// print(i+1);
}
boolean b = cstmt.execute();
// 获取输出参数的值
for (i = in.length;
i < output.length + in.length;
i++)
output[i - in.length] = cstmt.getObject(i + 1);
if (b) {
result = cstmt.getResultSet();
} else {
result = cstmt.getUpdateCount();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return result;
} // 时间转换
public static Date date(String date_str) {
try {
Calendar cal = Calendar.getInstance();
// 日期类
Timestamp timestampnow = new Timestamp(cal.getTimeInMillis());
// 转换成正常的日期格式
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
// 改为需要的东西
ParsePosition pos = new ParsePosition(0);
java.util.Date current = formatter.parse(date_str, pos);
timestampnow = new Timestamp(current.getTime());
return timestampnow;
} catch (NullPointerException e) {
return null;
}
}}
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