blocks|key|2047084|text|使用以下任一选项：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2047085|CurrentClassName.class.getResourceAsStream+
new+FileInputStream(File)|code-block|syntax|javascript|2047086|来获取输入流，这取决于类是在类路径中还是在类路径之外。然后使用|2047087|Properties.load|2047088|加载属性。|2047089|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Use either:

<pre><code>CurrentClassName.class.getResourceAsStream 
new FileInputStream(File)
</code></pre>

to get the input stream depending on if the class is in or out of the classpath. Then use

<pre><code>Properties.load
</code></pre>

to load the properties.

blocks|key|2047103|text|已经有一段时间了，但是如果我没记错的话，你可以这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2047104|Properties+prop+=+new+Properties();
prop.load(new+FileInputStream(filename));

//For+each+property+you+need.
blah+=+prop.getProperty(propertyname);|code-block|syntax|javascript|2047105|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

It's been a while, but if I remember correctly you just do something like this:

<pre><code>Properties prop = new Properties();
prop.load(new FileInputStream(filename));

//For each property you need.
blah = prop.getProperty(propertyname);
</code></pre>

blocks|key|2047154|text|嗯，对于静态属性，将它们初始化为Singleton是有意义的，它将在类中加载一次。下面是一个例子：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2047155|class+Example
{
++++public+final+static+String+PROPSFILE+=+"test.properties";

++++private+static+Properties+props;

++++protected+static+Properties+getProperties()
++++{
++++++++if(props+==+null)
++++++++{
++++++++++++props+=+new+Properties();
++++++++++++props.load(new+FileInputStream(new+File(PROPSFILE));
++++++++}
++++++++return+props;
++++}

++++public+static+User+getUser()
++++{
++++++++String+username+=+getProperties().getProperty("username");
++++++++return+new+User(username);
++++}
}|code-block|syntax|javascript|2047156|如果您使用相对路径名，您应该确保您的类路径设置正确。|2047157|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Well with static Properties it would make sense to initialize them as a Singleton which will be loaded once in a class. Here's an example:

<pre><code>class Example
{
 public final static String PROPSFILE = "test.properties";

 private static Properties props;

 protected static Properties getProperties()
 {
 if(props == null)
 {
 props = new Properties();
 props.load(new FileInputStream(new File(PROPSFILE));
 }
 return props;
 }

 public static User getUser()
 {
 String username = getProperties().getProperty("username");
 return new User(username);
 }
}
</code></pre>

If you use relative Pathnames you should make sure, that your classpath is setup righ.

blocks|key|1833011|text|我同意@Daff，也许在我的项目中使用单例class...this来满足类似的需求会更好，也许它会有所帮助：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1833012|类的客户端可以像这样使用它：|1833013|ConfigsLoader+configsLoader+=+ConfigsLoader.getInstance("etc/configs.xml");

System.out.format("source+dir+%25s+%25n",+configsLoader.getSourceDir());|code-block|syntax|javascript|1833014|然后是这个类：|1833015|公共类ConfigsLoader+{|1833016|private+String+sourceDir;
private+String+destination;
private+String+activeMqUrl;

private+static+Logger+log+=+Logger.getLogger(ConfigsLoader.class.getName());

private+static+ConfigsLoader+instance+=+null;

private+ConfigsLoader(String+configFileName)+{
++++log.info("loading+configs");
++++Properties+configs+=+new+Properties();
++++try+{
++++++++configs.loadFromXML(new+FileInputStream(configFileName));

++++++++sourceDir+=+configs.getProperty("source.dir");
++++++++destination+=+configs.getProperty("destination");
++++++++activeMqUrl+=+configs.getProperty("activemqconnectionurl");
++++++++configs.setProperty("lastLoaded",+new+SimpleDateFormat("yyyy-M-d+HH:mm").format(new+Date()));
++++++++configs.storeToXML(new+FileOutputStream(configFileName),+"saving+last+modified+dates");

++++}+catch+(InvalidPropertiesFormatException+e)+{
++++++++log.log(Level.SEVERE,"Error+occured+loading+the+properties+file"+,e);
++++}+catch+(FileNotFoundException+e)+{
++++++++log.log(Level.SEVERE,"Error+occured+loading+the+properties+file"+,e);
++++}+catch+(IOException+e)+{
++++++++log.log(Level.SEVERE,"Error+occured+loading+the+properties+file"+,e);
++++}
}

public+static+ConfigsLoader+getInstance(String+configFileName)+{
++++if(instance+==null)+{
++++++++instance+=+new+ConfigsLoader(configFileName);
++++}

++++return+instance;
}

public+String+getSourceDir()+{
++++return+sourceDir;
}

public+void+setSourceDir(String+sourceDir)+{
++++this.sourceDir+=+sourceDir;
}

public+String+getDestination()+{
++++return+destination;
}

public+void+setDestination(String+destination)+{
++++this.destination+=+destination;
}

public+String+getActiveMqUrl()+{
++++return+activeMqUrl;
}

public+void+setActiveMqUrl(String+activeMqUrl)+{
++++this.activeMqUrl+=+activeMqUrl;
}|1833017|}|1833018|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|V|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|F|7|X|8|@]|9|@]|A|$G|H]]|$1|O|3|P|5|6|7|Y|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

I agree with @Daff, maybe better to use singleton class...this what i have on my project for similar requirement, maybe it may help:

clients of the class can use it like this:

<pre><code>ConfigsLoader configsLoader = ConfigsLoader.getInstance("etc/configs.xml");

System.out.format("source dir %s %n", configsLoader.getSourceDir());
</code></pre>

and then the class:

public class ConfigsLoader {

<pre><code>private String sourceDir;
private String destination;
private String activeMqUrl;

private static Logger log = Logger.getLogger(ConfigsLoader.class.getName());

private static ConfigsLoader instance = null;

private ConfigsLoader(String configFileName) {
 log.info("loading configs");
 Properties configs = new Properties();
 try {
 configs.loadFromXML(new FileInputStream(configFileName));

 sourceDir = configs.getProperty("source.dir");
 destination = configs.getProperty("destination");
 activeMqUrl = configs.getProperty("activemqconnectionurl");
 configs.setProperty("lastLoaded", new SimpleDateFormat("yyyy-M-d HH:mm").format(new Date()));
 configs.storeToXML(new FileOutputStream(configFileName), "saving last modified dates");

 } catch (InvalidPropertiesFormatException e) {
 log.log(Level.SEVERE,"Error occured loading the properties file" ,e);
 } catch (FileNotFoundException e) {
 log.log(Level.SEVERE,"Error occured loading the properties file" ,e);
 } catch (IOException e) {
 log.log(Level.SEVERE,"Error occured loading the properties file" ,e);
 }
}

public static ConfigsLoader getInstance(String configFileName) {
 if(instance ==null) {
 instance = new ConfigsLoader(configFileName);
 }

 return instance;
}

public String getSourceDir() {
 return sourceDir;
}

public void setSourceDir(String sourceDir) {
 this.sourceDir = sourceDir;
}

public String getDestination() {
 return destination;
}

public void setDestination(String destination) {
 this.destination = destination;
}

public String getActiveMqUrl() {
 return activeMqUrl;
}

public void setActiveMqUrl(String activeMqUrl) {
 this.activeMqUrl = activeMqUrl;
}
</code></pre>

}

blocks|key|1833072|text|最后，我使用与编写静态代码块的类相关的getResourceAsStream()函数完成了这项工作。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1833073|//associate+Property+and+ImputStream+imports
public+class+A+{
++++static+Properties+p;
++++static+{
++++++p+=+new+Properties();
++++++try+{
++++++++++InputStream+in+=+A.class.getResourceAsStream("filename.properties");
++++++++++p.load(in);
++++++}+catch+(FileNotFoundException+e)+{
++++++++System.out.println("FileNotFoundException");
++++++++e.printStackTrace();
++++++}+catch+(IOException+e)+{
++++++++System.out.println("IOException");
++++++++e.printStackTrace();
++++++}
++++}
++++.
++++.
++++.
}|code-block|syntax|javascript|1833074|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I did this finally using getResourceAsStream() fuction associated with the class in which the static code block is being written.

<pre><code>//associate Property and ImputStream imports
public class A {
 static Properties p;
 static {
 p = new Properties();
 try {
 InputStream in = A.class.getResourceAsStream("filename.properties");
 p.load(in);
 } catch (FileNotFoundException e) {
 System.out.println("FileNotFoundException");
 e.printStackTrace();
 } catch (IOException e) {
 System.out.println("IOException");
 e.printStackTrace();
 }
 }
 .
 .
 .
}
</code></pre>

blocks|key|1833103|text|对我来说，MyClass.class.getClassLoader().getResourceAsStream(..)做到了：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1833104|private+static+final+Properties+properties;

static+{
++++Properties+fallback+=+new+Properties();
++++fallback.put(PROP_KEY,+FALLBACK_VALUE);

++++properties+=+new+Properties(fallback);

++++try+{
++++++++try+(InputStream+stream+=+MyClass.class.getClassLoader().getResourceAsStream("myProperties.properties"))+{
++++++++++++properties.load(stream);
++++++++}
++++}+catch+(IOException+ex)+{
++++++++//+handle+error
++++}
}|code-block|syntax|javascript|1833105|entityMap^0|5|1I|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

for me <code>MyClass.class.getClassLoader().getResourceAsStream(..)</code> did the trick:

<pre><code>private static final Properties properties;

static {
 Properties fallback = new Properties();
 fallback.put(PROP_KEY, FALLBACK_VALUE);

 properties = new Properties(fallback);

 try {
 try (InputStream stream = MyClass.class.getClassLoader().getResourceAsStream("myProperties.properties")) {
 properties.load(stream);
 }
 } catch (IOException ex) {
 // handle error
 }
}
</code></pre>

I have a static util class that does some string manipulation on a bit sensitive data.
Prior to use of this class I need to initialize certain static variables with values, such as usernames/password, that I prefer to store in a <code>.properties</code> file.

I am not very familiar with how loading of <code>.properties</code> file work in Java, especially outside of *Spring DI *container.
Anyone can give me a hand/insight on how this can be done?

Thank you!

Addition: <code>.properties</code> file precise location is unknown, but it will be on the classpath. Sorta like <code>classpath:/my/folder/name/myproperties.propeties</code>

Load java properties inside static initializer block

容器

Java

我有一个静态的util类，它对一些敏感数据进行一些字符串操作。在使用这个类之前，我需要用我喜欢存储在.properties文件中的值来初始化某些静态变量，比如用户名/密码。我不太熟悉在Java语言中如何加载.properties文件，尤其是在*Spring DI *容器之外。有没有人能给我一些帮助/建议？谢谢!另外：....

问在静态初始值设定项块内加载java属性
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