如何解決spring無法讀取properties文件數據問題

本篇文章為大家展示了如何解決spring無法讀取properties文件數據問題，內容簡明扼要并且容易理解，絕對能使你眼前一亮，通過這篇文章的詳細介紹希望你能有所收獲。

1. controller中無法讀取config.properties文件

controller中注入的@Value配置是從servlet-context.xml配置文件中獲取的；service中注入的@Value配置可以從applicationContext.xml中獲取的。所以，如果要在controller中注入屬性配置，需要在相應servlet文件中添加配置，同applicationContext.xml中一樣。

<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">  <property name="locations">    <list>       <value>classpath:jdbc.properties</value>      <value>classpath:config.properties</value>     </list>  </property>  <property name="ignoreUnresolvablePlaceholders" value="true"/></bean>

2.service中無法讀取config.properties文件

查看配置文件是否有多個。如果配置的路徑是classpath:config.properties, 鼠標點擊文件。如果顯示”multiple implementations”, 表示有多個文件，查看其他的文件中是否有需要的配置項，沒有的話，很可能就是加載了其他文件的配置項。這時，將路徑改為classpath*:config.properties即可。

<context:property-placeholder   ignore-unresolvable="true" location="classpath:/jdbc.properties, classpath*:/config.properties"/>

查看日志，發現：

[2017-01-05 16:45:02 INFO ] [main] (org.springframework.context.support.PropertySourcesPlaceholderConfigurer:?) - Loading properties file from URL [jar:file:/home/admin/creative-task/lib/xxxx-common-1.5.7.jar!/config.properties][2017-01-05 16:45:02 INFO ] [main] (org.springframework.context.support.PropertySourcesPlaceholderConfigurer:?) - Loading properties file from URL 下載地址

加載了兩個config.properties文件。

3.關于診斷：

1）首先確認是否正確加載了配置文件。查看日志：

正常日志如下：

[2017-01-05 16:45:02 INFO ] [main] (org.springframework.context.support.PropertySourcesPlaceholderConfigurer:?) - Loading properties file from URL 下載地址

 異常日志如下：

[2017-01-05 16:39:39 ERROR] [main] (Main:22) - Could not load properties; nested exception is java.io.FileNotFoundException: class path resource [config.properties] cannot be opened because it does not existorg.springframework.beans.factory.BeanInitializationException: Could not load properties; nested exception is java.io.FileNotFoundException: class path resource [config.properties] cannot be opened because it does not exist

如果文件沒有加載，則查看路徑是否匹配等。

2）如果文件加載ok，查看配置屬性是否正確加載。

查看tomcat啟動的debug日志：

正常日志如下：

[2017-01-05 16:45:04 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Searching for key 'adx.id' in [environmentProperties][2017-01-05 16:45:04 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Searching for key 'adx.id' in [systemProperties][2017-01-05 16:45:04 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Searching for key 'adx.id' in [systemEnvironment][2017-01-05 16:45:04 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Could not find key 'adx.id' in any property source. Returning [null][2017-01-05 16:45:04 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Searching for key 'adx.id' in [localProperties][2017-01-05 16:45:04 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Found key 'adx.id' in [localProperties] with type [String] and value '1'

異常日志如下：

[2017-01-05 16:34:01 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Searching for key 'adx.id' in [environmentProperties][2017-01-05 16:34:01 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Searching for key 'adx.id' in [systemProperties][2017-01-05 16:34:01 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Searching for key 'adx.id' in [systemEnvironment][2017-01-05 16:34:01 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Could not find key 'adx.id' in any property source. Returning [null][2017-01-05 16:34:01 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Searching for key 'adx.id' in [localProperties][2017-01-05 16:34:01 DEBUG] [main] (org.springframework.core.env.PropertySourcesPropertyResolver:?) - Could not find key 'adx.id' in any property source. Returning [null]

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