連線資料庫時錯誤資訊如下

16:10:47.547 [Druid-ConnectionPool-Create-574835454] ERROR c.alibaba.druid.pool.DruidDataSource - create connection SQLException, url: jdbc:oracle:thin:@192.168.1.2:1521:orcl, errorCode 1017, state 72000
java.sql.SQLException: ORA-01017: invalid username/password; logon denied
    at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:447
 
) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:389) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:382) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.T4CTTIfun.processError(T4CTTIfun.java:675) ~[ojdbc-6.jar:11.2.0
 
.3.0]
    at oracle.jdbc.driver.T4CTTIoauthenticate.processError(T4CTTIoauthenticate.java:448) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:513) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:227) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.T4CTTIoauthenticate.doOAUTH(T4CTTIoauthenticate.java:383
 
) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.T4CTTIoauthenticate.doOAUTH(T4CTTIoauthenticate.java:776) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:432) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:553) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:254) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:32) ~[ojdbc-6.jar:11.2.0.3.0]
    at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:528) ~[ojdbc-6.jar:11.2.0.3.0]
    at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:149) ~[druid-1.1.9.jar:1.1.9]
    at com.alibaba.druid.filter.stat.StatFilter.connection_connect(StatFilter.java:218) ~[druid-1.1.9.jar:1.1.9]
    at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:143) ~[druid-1.1.9.jar:1.1.9]
    at com.alibaba.druid.filter.FilterAdapter.connection_connect(FilterAdapter.java:786) ~[druid-1.1.9.jar:1.1.9]
    at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:143) ~[druid-1.1.9.jar:1.1.9]
    at com.alibaba.druid.filter.stat.StatFilter.connection_connect(StatFilter.java:218) ~[druid-1.1.9.jar:1.1.9]
    at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:143) ~[druid-1.1.9.jar:1.1.9]
    at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1515) ~[druid-1.1.9.jar:1.1.9]
    at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1578) ~[druid-1.1.9.jar:1.1.9]
    at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466) ~[druid-1.1.9.jar:1.1.9]

解決如下：

1. 檢查配置檔案是否寫錯，大小寫是否正確

2. 如果都沒有問題的話，檢查使用者名稱是否直接使用的${username}

   如果是 2中${username} 的情況，可以修改配置檔案中username屬性名，新增字首或者字尾，確保引用時不是${username}即可，或者可以在引用配置檔案時使用如下system-properties-mode屬性

   <context:property-placeholder location="classpath:jdbc.properties" system-properties-mode="FALLBACK" />