Apache Commons 配置 - PropertiesConfiguration 已关闭

Question

PropertiesConfiguration.java 没有 close() 方法。是否需要做其他事情来释放文件？在生产中使用它之前，我想确定一下。我查看了代码，但没有看到任何内容。我不完全确定 PropertiesConfiguration.setProperty() 在不打开与随后必须关闭的文件的连接的情况下如何工作。

Answer 1

在 org.apache.commons.configuration.PropertiesConfiguration 中，当在 PropertiesConfiguration 实例中加载属性时，输入（流、路径、url 等...）当然会关闭。

你可以在org.apache.commons.configuration.AbstractFileConfiguration的void load(URL url)方法中得到确认。

调用此方法的方式如下：

1) PropertiesConfiguration 构造函数被调用：

public PropertiesConfiguration(File file) throws ConfigurationException

2) 调用其超级构造函数：

public AbstractFileConfiguration(File file) throws ConfigurationException
{
    this();

    // set the file and update the url, the base path and the file name
    setFile(file);

    // load the file
    if (file.exists())
    {
        load(); // method which interest you
    }
}

3) 调用 load() :

public void load() throws ConfigurationException
{
    if (sourceURL != null)
    {
        load(sourceURL);
    }
    else
    {
        load(getFileName());
    }
}

4) 调用 load(String fileName):

public void load(String fileName) throws ConfigurationException
{
    try
    {
        URL url = ConfigurationUtils.locate(this.fileSystem, basePath, fileName);

        if (url == null)
        {
            throw new ConfigurationException("Cannot locate configuration source " + fileName);
        }
        load(url);
    }
    catch (ConfigurationException e)
    {
        throw e;
    }
    catch (Exception e)
    {
        throw new ConfigurationException("Unable to load the configuration file " + fileName, e);
    }
}

5) 调用 load(URL url)

public void load(URL url) throws ConfigurationException
{
    if (sourceURL == null)
    {
        if (StringUtils.isEmpty(getBasePath()))
        {
            // ensure that we have a valid base path
            setBasePath(url.toString());
        }
        sourceURL = url;
    }

    InputStream in = null;

    try
    {
        in = fileSystem.getInputStream(url);
        load(in);
    }
    catch (ConfigurationException e)
    {
        throw e;
    }
    catch (Exception e)
    {
        throw new ConfigurationException("Unable to load the configuration from the URL " + url, e);
    }
    finally
    {
        // close the input stream
        try
        {
            if (in != null)
            {
                in.close();
            }
        }
        catch (IOException e)
        {
            getLogger().warn("Could not close input stream", e);
        }
    }
}

并且在finally语句中，可以看到inputstream在任何情况下都是关闭的。

Apache Commons 配置 - PropertiesConfiguration 已关闭

Apache Commons Configuration - PropertiesConfiguration closed

java

io

properties-file