mysql-数据类型与java数据类型转化工具类

mysql和java对照表

类型名称	显示长度	数据库类型	JAVA类型	JDBC类型索引(int)	描述
VARCHAR	L+N	VARCHAR	java.lang.String	12
CHAR	N	CHAR	java.lang.String	1
BLOB	L+N	BLOB	java.lang.byte[]	-4
TEXT	65535	VARCHAR	java.lang.String	-1
INTEGER	4	INTEGER UNSIGNED	java.lang.Long	4
TINYINT	3	TINYINT UNSIGNED	java.lang.Integer	-6
SMALLINT	5	SMALLINT UNSIGNED	java.lang.Integer	5
MEDIUMINT	8	MEDIUMINT UNSIGNED	java.lang.Integer	4
BIT	1	BIT	java.lang.Boolean	-7
BIGINT	20	BIGINT UNSIGNED	java.math.BigInteger	-5
FLOAT	4+8	FLOAT	java.lang.Float	7
DOUBLE	22	DOUBLE	java.lang.Double	8
DECIMAL	11	DECIMAL	java.math.BigDecimal	3
BOOLEAN	1	同TINYINT
ID	11	PK (INTEGER UNSIGNED)	java.lang.Long	4
DATE	10	DATE	java.sql.Date	91
TIME	8	TIME	java.sql.Time	92
DATETIME	19	DATETIME	java.sql.Timestamp	93
TIMESTAMP	19	TIMESTAMP	java.sql.Timestamp	93
YEAR	4	YEAR	java.sql.Date	91

对于bolb，一般用于对图片的数据库存储，原理是把图片打成二进制，然后进行的一种存储方式，在java中对应byte［］数组。

对于boolen类型，在mysql数据库中，个人认为用int类型代替较好，对bit操作不是很方便，尤其是在具有web页面开发的项目中，表示0/1，对应java类型的Integer较好。

/**
* 数据类型转化JAVA
* @param sqlType：类型名称
* @return
*/
public static String toSqlToJava(String sqlType) {
if( sqlType == null || sqlType.trim().length() == 0 ) return sqlType;
sqlType = sqlType.toLowerCase();
switch(sqlType){
case "nvarchar":return "String";
case "char":return "String";
case "varchar":return "String";
case "text":return "String";
case "nchar":return "String";
case "blob":return "byte[]";
case "integer":return "Long";
case "tinyint":return "Integer";
case "smallint":return "Integer";
case "mediumint":return "Integer";
case "bit":return "Boolean";
case "bigint":return "java.math.BigInteger";
case "float":return "Fload";
case "double":return "Double";
case "decimal":return "java.math.BigDecimal";
case "boolean":return "Boolean";
case "id":return "Long";
case "date":return "java.util.Date";
case "datetime":return "java.util.Date";
case "year":return "java.util.Date";
case "time":return "java.sql.Time";
case "timestamp":return "java.sql.Timestamp";
case "numeric":return "java.math.BigDecimal";
case "real":return "java.math.BigDecimal";
case "money":return "Double";
case "smallmoney":return "Double";
case "image":return "byte[]";
default:
System.out.println("-----------------》转化失败：未发现的类型"+sqlType);
break;
}
return sqlType;
}