blocks|key|253908|text|你有没有考虑过在构造函数中设置或者在主体中@Autowired和String.split()？|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|253909|class+MyClass+{
++++private+List<String>+myList;

++++@Autowired
++++public+MyClass(@Value("${my.list.of.strings}")+final+String+strs)+{
++++++++myList+=+Arrays.asList(strs.split(","));
++++}

++++//or

++++@Autowired
++++public+void+setMyList(@Value("${my.list.of.strings}")+final+String+strs)+{
++++++++myList+=+Arrays.asList(strs.split(","));
++++}
}|code-block|syntax|javascript|253910|为了增强代码的可测试性，我倾向于使用这些方法中的一种来进行自动装配。|253911|entityMap^0|L|A|W|E|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|N|$]]

Have you considered <code>@Autowired</code>ing the constructor or a setter and <code>String.split()</code>ing in the body?

<pre><code>class MyClass {
 private List&lt;String&gt; myList;

 @Autowired
 public MyClass(@Value("${my.list.of.strings}") final String strs) {
 myList = Arrays.asList(strs.split(","));
 }

 //or

 @Autowired
 public void setMyList(@Value("${my.list.of.strings}") final String strs) {
 myList = Arrays.asList(strs.split(","));
 }
}
</code></pre>

I tend to prefer doing my autowiring in one of these ways to enhance the testability of my code.

blocks|key|470865|text|通过在.properties文件中指定my.list.of.strings=ABC,CDE,EFG并使用|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|470866|@Value("${my.list.of.strings}")+private+String[]+myString;|470867|您可以获取字符串数组。使用CollectionUtils.addAll(myList,+myString)，您可以获得字符串列表。|470868|entityMap^0|J|U|0|0|V|W|Q|0|D|14|0^^$0|@$1|2|3|4|5|6|7|L|8|@$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|T|8|@$9|U|A|V|B|C]]|D|@]|E|$]]|$1|J|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|K|$]]

By specifying the the <code>my.list.of.strings=ABC,CDE,EFG</code> in .properties file and using 

<code>@Value("${my.list.of.strings}")</code>
<code>private String[] myString;</code>

You can get the arrays of strings. And using <code>CollectionUtils.addAll(myList, myString)</code>, you can get the list of strings.

blocks|key|470928|text|以上所有答案都是正确的。但是您可以在一行代码中实现这一点。请尝试下面的声明，您将在字符串列表中获得所有逗号分隔值。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|470929|private+@Value("#{T(java.util.Arrays).asList(projectProperties['my.list.of.strings'])}")+List<String>+myList;|code-block|syntax|javascript|470930|此外，还需要在xml配置中定义以下行。|470931|<util:properties+id="projectProperties"+location="/project.properties"/>|470932|只需替换属性文件的路径和文件名即可。你就可以走了。:)|470933|希望这对你有帮助。干杯。|470934|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|V|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

All the above answers are correct. But you can achieve this in just one line.
Please try following declaration and you will get all the comma separated values in a String list.

<pre><code>private @Value("#{T(java.util.Arrays).asList(projectProperties['my.list.of.strings'])}") List&lt;String&gt; myList;
</code></pre>

And also you need to have the following line defined in your xml configuration.

<pre><code>&lt;util:properties id="projectProperties" location="/project.properties"/&gt;
</code></pre>

just replace the path and file name of your properties file. And you are good to go. :)

Hope this helps you. Cheers.

blocks|key|254037|text|使用Spring+EL：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|254038|@Value("#{'${my.list.of.strings}'.split(',')}")+
private+List<String>+myList;|code-block|syntax|javascript|254039|假设您的属性文件已正确加载，并具有以下内容：|254040|my.list.of.strings=ABC,CDE,EFG|254041|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Using Spring EL:

<pre><code>@Value("#{'${my.list.of.strings}'.split(',')}") 
private List&lt;String&gt; myList;
</code></pre>

Assuming your properties file is loaded correctly with the following:

<pre><code>my.list.of.strings=ABC,CDE,EFG
</code></pre>

blocks|key|470998|text|您可以使用如下所示的注释来完成此操作|type|unstyled|depth|inlineStyleRanges|entityRanges|data|470999|+@Value("#{T(java.util.Arrays).asList('${my.list.of.strings:a,b,c}')}")+
++++private+List<String>+mylist;|code-block|syntax|javascript|471000|在这里，将从属性文件中选取my.list.of.strings，如果它不在那里，那么将使用默认值a、b、c|471001|在你的属性文件中，你可以有类似这样的东西|471002|my.list.of.strings=d、e、f|471003|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]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

you can do this with annotations like this

<pre><code> @Value("#{T(java.util.Arrays).asList('${my.list.of.strings:a,b,c}')}") 
 private List&lt;String&gt; mylist;
</code></pre>

here my.list.of.strings will be picked from the properties file, if its not there, then the defaults a,b,c will be used

and in your properties file, you can have something like this

my.list.of.strings=d,e,f

blocks|key|254134|text|如果使用属性占位符，则ser1702544示例将变为|type|unstyled|depth|inlineStyleRanges|entityRanges|data|254135|@Value("#{myConfigProperties['myproperty'].trim().replaceAll(\"\\s*(?=,)%7C(?<=,)\\s*\",+\"\").split(',')}")+|code-block|syntax|javascript|254136|使用占位符xml：|254137|<bean+class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">+++
++++<property+name="properties"+ref="myConfigProperties"+/>
++++<property+name="placeholderPrefix"><value>$myConfigProperties{</value></property>
</bean>++++

<bean+id="myConfigProperties"+class="org.springframework.beans.factory.config.PropertiesFactoryBean">
+++++<property+name="locations">
+++++++++<list>
++++++++++++++++<value>classpath:myprops.properties</value>
+++++++++</list>
+++++</property>
</bean>+|254138|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

if using property placeholders then ser1702544 example would become 

<pre><code>@Value("#{myConfigProperties['myproperty'].trim().replaceAll(\"\\s*(?=,)|(?&lt;=,)\\s*\", \"\").split(',')}") 
</code></pre>

With placeholder xml:

<pre><code>&lt;bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"&gt; 
 &lt;property name="properties" ref="myConfigProperties" /&gt;
 &lt;property name="placeholderPrefix"&gt;&lt;value&gt;$myConfigProperties{&lt;/value&gt;&lt;/property&gt;
&lt;/bean&gt; 

&lt;bean id="myConfigProperties" class="org.springframework.beans.factory.config.PropertiesFactoryBean"&gt;
 &lt;property name="locations"&gt;
 &lt;list&gt;
 &lt;value&gt;classpath:myprops.properties&lt;/value&gt;
 &lt;/list&gt;
 &lt;/property&gt;
&lt;/bean&gt; 
</code></pre>

blocks|key|254150|text|我认为这对于获取数组和剥离空格更简单：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|254151|@Value("#{'${my.array}'.replace('+',+'').split(',')}")
private+List<String>+array;|code-block|syntax|javascript|254152|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 think this is simpler for grabbing the array and stripping spaces:

<pre><code>@Value("#{'${my.array}'.replace(' ', '').split(',')}")
private List&lt;String&gt; array;
</code></pre>

blocks|key|471136|text|如果你使用的是最新的Spring框架版本(我相信是Spring+3.1%2B+)，你就不需要在SpringEL中拆分字符串，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|471137|只需在Spring的Configuration类(带有Configuration注释的类)中添加PropertySourcesPlaceholderConfigurer和DefaultConversionService，例如，|471138|@Configuration
public+class+AppConfiguration+{

++++@Bean
++++public+static+PropertySourcesPlaceholderConfigurer+propertyPlaceholderConfigurer()+{
++++++++return+new+PropertySourcesPlaceholderConfigurer();
++++}

++++@Bean+public+ConversionService+conversionService()+{
++++++++return+new+DefaultConversionService();
++++}
}|code-block|syntax|javascript|471139|在你的班上|471140|@Value("${list}")
private+List<String>+list;|471141|并在属性文件中|471142|list=A,B,C,D,E|471143|没有DefaultConversionService，当你将值注入字段时，你只能将逗号分隔的字符串放入字符串数组中，但是DefaultConversionService为你做了一些方便的魔术，并会将它们添加到集合、数组等中(如果你想了解更多信息，请查看实现)|471144|有了这两个，它甚至可以处理所有多余的空格，包括换行符，所以你不需要添加额外的逻辑来修剪它们。|471145|entityMap^0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|Z|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|10|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|11|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|12|8|@]|9|@]|A|$G|H]]|$1|Q|3|R|5|6|7|13|8|@]|9|@]|A|$]]|$1|S|3|T|5|6|7|14|8|@]|9|@]|A|$]]|$1|U|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|V|$]]

If you are using latest Spring framework version(Spring 3.1+ I believe), you don't need to those string split stuff in SpringEL,

Simply add PropertySourcesPlaceholderConfigurer and DefaultConversionService in your Spring's Configuration class ( the one with annotated with Configuration ) e.g, 

<pre><code>@Configuration
public class AppConfiguration {

 @Bean
 public static PropertySourcesPlaceholderConfigurer propertyPlaceholderConfigurer() {
 return new PropertySourcesPlaceholderConfigurer();
 }

 @Bean public ConversionService conversionService() {
 return new DefaultConversionService();
 }
}
</code></pre>

and in your class 

<pre><code>@Value("${list}")
private List&lt;String&gt; list;
</code></pre>

and in the properties file

<pre><code>list=A,B,C,D,E
</code></pre>

Without DefaultConversionService, you can only take comma separated String into String array when you inject the value into your field, but DefaultConversionService does a few convenient magic for you and will add those into Collection, Array, etc. ( check the implementation if you'd like to know more about it )

With these two, it even handles all the redundant whitespaces including newline, so you don't need to add additional logics to trim them.

blocks|key|254272|text|如果您使用的是Spring+Boot+2，它将按原样工作，不需要任何额外的配置。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|254273|my.list.of.strings=ABC,CDE,EFG

@Value("${my.list.of.strings}")
private+List<String>+myList;|code-block|syntax|javascript|254274|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|$]]

If you are using Spring Boot 2, it works as is, without any additional configuration.

<pre><code>my.list.of.strings=ABC,CDE,EFG

@Value("${my.list.of.strings}")
private List&lt;String&gt; myList;
</code></pre>

blocks|key|471206|text|在我使用整数列表的情况下，如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|471207|@Value("#{${my.list.of.integers}}")
private+List<Integer>+listOfIntegers;|code-block|syntax|javascript|471208|属性文件：|471209|my.list.of.integers={100,200,300,400,999}|471210|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

In my case of a list of integers works this:

<pre><code>@Value("#{${my.list.of.integers}}")
private List&lt;Integer&gt; listOfIntegers;
</code></pre>

Property file:

<pre><code>my.list.of.integers={100,200,300,400,999}
</code></pre>

blocks|key|471238|text|我的首选方式(特别是字符串)是以下方式：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|471239|admin.user={'Doe,+John','Headroom,+Max','Mouse,+Micky'}|code-block|syntax|javascript|471240|并使用|471241|@Value("#{${admin.user}}")
private+List<String>+userList;|471242|这样，您还可以在参数中包含逗号。它也适用于集合。|471243|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|$]]

My preferred way (for strings, in particular), is the following one:

<pre><code>admin.user={'Doe, John','Headroom, Max','Mouse, Micky'}
</code></pre>

and use 

<pre><code>@Value("#{${admin.user}}")
private List&lt;String&gt; userList;
</code></pre>

In this way, you can include also commas in your parameter. It works also for Sets.

blocks|key|471273|text|我使用的是Spring+Boot+2.2.6|type|unstyled|depth|inlineStyleRanges|entityRanges|data|471274|我的属性文件：|471275|usa.big.banks=+JP+Morgan,+Wells+Fargo,+Citigroup,+Morgan+Stanley,+Goldman+Sachs|code-block|syntax|javascript|471276|我的代码：|471277|@Value("${usa.big.banks}")
++++private+List<String>+bigBanks;

@RequestMapping("/bigbanks")
++++public+String+getBanks()+{
++++++++System.out.println("bigBanks+=+"+%2B+bigBanks);
++++++++return+bigBanks.toString();
++++}|471278|它工作正常|471279|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|R|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|T|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|U|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|V|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

I am using Spring Boot 2.2.6

My property file:

<pre><code>usa.big.banks= JP Morgan, Wells Fargo, Citigroup, Morgan Stanley, Goldman Sachs
</code></pre>

My code:

<pre><code>@Value("${usa.big.banks}")
 private List&lt;String&gt; bigBanks;

@RequestMapping("/bigbanks")
 public String getBanks() {
 System.out.println("bigBanks = " + bigBanks);
 return bigBanks.toString();
 }
</code></pre>

It works fine

blocks|key|254403|text|答案|type|unstyled|depth|inlineStyleRanges|entityRanges|data|254404|@Value("#{'${my.list.of.strings}'.split(',')}")+
private+List<String>+myList;+|code-block|syntax|javascript|254405|对于逗号分隔值，工作方式与预期相同。要处理null+(如果未指定属性)，请将默认值(属性名称后的':+')作为空字符串添加，如下所示：|offset|length|style|CODE|254406|@Value("#{'${my.list.of.strings:+}'.split(',')}")|254407|entityMap^0|0|0|1C|4|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@$I|T|J|U|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

The Answer
<pre><code>@Value(&quot;#{'${my.list.of.strings}'.split(',')}&quot;) 
private List&lt;String&gt; myList; 
</code></pre>
works as expected for the comma separated values.
To handle null (when property not specified) added the default value(<code>': '</code>after the property name) as empty string as below:
<pre><code>@Value(&quot;#{'${my.list.of.strings: }'.split(',')}&quot;)
</code></pre>

I want to have a list of values in a .properties file, ie:

<pre><code>my.list.of.strings=ABC,CDE,EFG
</code></pre>

And to load it in my class directly, ie:

<pre><code>@Value("${my.list.of.strings}")
private List&lt;String&gt; myList;
</code></pre>

As I understand, an alternative of doing this is to have it in the spring config file, and load it as a bean reference (correct me if I'm wrong), ie

<pre><code>&lt;bean name="list"&gt;
 &lt;list&gt;
 &lt;value&gt;ABC&lt;/value&gt;
 &lt;value&gt;CDE&lt;/value&gt;
 &lt;value&gt;EFG&lt;/value&gt;
 &lt;/list&gt;
&lt;/bean&gt;
</code></pre>

But is there any way of doing this? using a .properties file? 
ps: I would like to do this with out any custom code if possible.

Reading a List from properties file and load with spring annotation @Value

Spring Boot

我希望在.properties文件中有一个值列表，即：my.list.of.strings=ABC,CDE,EFG并将其直接加载到我的类中，即：@Value("${my.list.of.strings}")private List<String> myList;据我所知，这样做的另一种选择是将它放在spring配置文件...

问从属性文件中读取列表，并使用spring注解@Value加载
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