Java中枚举类型Enum的一种使用方式

来源：互联网发布：scientific linux 6 编辑：程序博客网时间：2024/06/05 08:29

枚举类定义如下：

public enum Status {    SCUUESS("1", "成功"), FAILED("2", "失败");    private String value;    private String desc;    public String getValue() {        return value;    }    public void setValue(String value) {        this.value = value;    }    public String getDesc() {        return desc;    }    public void setDesc(String desc) {        this.desc = desc;    }    private Status(String value, String desc) {        this.value = value;        this.desc = desc;    }}

使用的方式如下：

public class StutusTest {    public static void main(String[] args) {        System.out.println(Status.SCUUESS.getValue());        System.out.println(Status.SCUUESS.getDesc());        System.out.println(Status.FAILED.getValue());        System.out.println(Status.FAILED.getDesc());    }}

这里写图片描述

再比如，我们在操作数据库的时候，通常使用数字保存到数据库中，但是在界面上显示的时候，需要展示其中文意思，南无我们就可以通过下边的方式：

public enum FlightType {    OW(1, "单程"), RT(2, "往返");    public Integer code;    public String desc;    FlightType(Integer code, String desc) {        this.code = code;        this.desc = desc;    }    public Integer getCode() {        return code;    }    public void setCode(Integer code) {        this.code = code;    }    public String getDesc() {        return desc;    }    public void setDesc(String desc) {        this.desc = desc;    }    public static FlightType getTypeByCode(Integer code) {        FlightType defaultType = FlightType.OW;        for (FlightType ftype : FlightType.values()) {            if (ftype.code == code) {                return ftype;            }        }        return defaultType;    }    public static String getDescByCode(Integer code) {        return getTypeByCode(code).desc;    }}

这样的话，我们就可以通过getDescByCode方法获得其对应的中文。

另外，参数的个数是可以进行变化的，例如下边：

public enum DatabaseType {    unknown(null, null, null,null),    mysql("com.mysql.jdbc.Driver", "com.mysql.jdbc.jdbc2.optional.MysqlXADataSource", "select 1",Dialect.MYSQL),    h2("org.h2.Driver", "org.h2.jdbcx.JdbcDataSource", "select 1",Dialect.H2),    oracle("oracle.jdbc.driver.OracleDriver", "oracle.jdbc.xa.client.OracleXADataSource", "select 1 from dual",Dialect.ORACLE);    DatabaseType(String driverClassName, String xaDataSourceClassName, String testQuery,Dialect dialect) {        this.driverClassName = driverClassName;        this.testQuery = testQuery;        this.xaDataSourceClassName = xaDataSourceClassName;        this.dialect=dialect;    }    private final String testQuery;    private final String driverClassName;    private final String xaDataSourceClassName;    private final Dialect dialect;    public String getDriverClassName() {        return driverClassName;    }    public String getXaDataSourceClassName() {        return xaDataSourceClassName;    }    public String getTestQuery() {        return testQuery;    }    public Dialect getDialect() {        return dialect;    }    public static DatabaseType fromJdbcUrl(String url) {        if (StringUtils.hasLength(url)) {            Assert.isTrue(url.startsWith("jdbc"), "URL must start with 'jdbc'");            String urlWithoutPrefix = url.substring("jdbc".length()).toLowerCase();            for (DatabaseType driver : values()) {                String prefix = ":" + driver.name().toLowerCase() + ":";                if (driver != unknown && urlWithoutPrefix.startsWith(prefix)) {                    return driver;                }            }        }        return unknown;    }}

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