使用Java中的configuration2读取逗号分隔的属性。

Question

我有一个属性：

move.patternfile.include = *1a.txt,*2a.txt

我正在尝试将其放入列表中，使用Apache commons configuration2。

我拥有的代码是：

Configurations configs = new Configurations();
AbstractConfiguration config = configs.properties(new File(fileName));
config.setListDelimiterHandler(new DefaultListDelimiterHandler(','));

我可以读取其他属性，但我想要的属性仍然是一个大小为1的列表。

这是检索值的命令：

List<String> linclude = configuration.getList(String.class, "patternfile.include");

您能帮忙吗？

- n savoini

---

你能试着在属性字段中的 * 字符后面添加两个 \（反斜杠）吗？ move.patternfile.include = \\*1a.txt, \\*2a.txt. 像这样？ - Ravindra Mijar

N savoini，它能工作吗？ - Ravindra Mijar

仍然没有...仍在寻找正确的方法来做到这一点。 - n savoini

Answer 1

根据这个，似乎在从文件读取属性之前必须设置定界符。当我运行下面的代码时，它可以正常工作，但会生成警告。

Parameters params = new Parameters();
FileBasedConfigurationBuilder<PropertiesConfiguration> builder =
     new FileBasedConfigurationBuilder<PropertiesConfiguration>(
             PropertiesConfiguration.class).configure(params.fileBased()
             .setListDelimiterHandler(new DefaultListDelimiterHandler(','))
             .setFile(new File("test.properties")));
PropertiesConfiguration config = builder.getConfiguration();

List<String> linclude = config.getList(String.class, "patternfile.include");

System.out.println(linclude.size());
for(String item: linclude){
    System.out.println(item);
}

test.properties

patternfile.include = *1a.txt,*2a.txt

输出

2

*1a.txt

*2a.txt

当我运行它时，我看到的警告如下：

Jun 26, 2016 2:12:17 AM org.apache.commons.beanutils.FluentPropertyBeanIntrospector introspect
WARNING: Error when creating PropertyDescriptor for public final void org.apache.commons.configuration2.AbstractConfiguration.setProperty(java.lang.String,java.lang.Object)! Ignoring this property.
java.beans.IntrospectionException: bad write method arg count: public final void org.apache.commons.configuration2.AbstractConfiguration.setProperty(java.lang.String,java.lang.Object)
    at java.beans.PropertyDescriptor.findPropertyType(Unknown Source)
    at java.beans.PropertyDescriptor.setWriteMethod(Unknown Source)
    at java.beans.PropertyDescriptor.<init>(Unknown Source)
    at org.apache.commons.beanutils.FluentPropertyBeanIntrospector.createFluentPropertyDescritor(FluentPropertyBeanIntrospector.java:177)
    at org.apache.commons.beanutils.FluentPropertyBeanIntrospector.introspect(FluentPropertyBeanIntrospector.java:140)
    at org.apache.commons.beanutils.PropertyUtilsBean.fetchIntrospectionData(PropertyUtilsBean.java:2234)
    at org.apache.commons.beanutils.PropertyUtilsBean.getIntrospectionData(PropertyUtilsBean.java:2215)
    at org.apache.commons.beanutils.PropertyUtilsBean.getPropertyDescriptor(PropertyUtilsBean.java:950)
    at org.apache.commons.beanutils.PropertyUtilsBean.isWriteable(PropertyUtilsBean.java:1466)
    at org.apache.commons.configuration2.beanutils.BeanHelper.isPropertyWriteable(BeanHelper.java:521)
    at org.apache.commons.configuration2.beanutils.BeanHelper.initProperty(BeanHelper.java:357)
    at org.apache.commons.configuration2.beanutils.BeanHelper.initBeanProperties(BeanHelper.java:273)
    at org.apache.commons.configuration2.beanutils.BeanHelper.initBean(BeanHelper.java:192)
    at org.apache.commons.configuration2.beanutils.BeanHelper$BeanCreationContextImpl.initBean(BeanHelper.java:669)
    at org.apache.commons.configuration2.beanutils.DefaultBeanFactory.initBeanInstance(DefaultBeanFactory.java:162)
    at org.apache.commons.configuration2.beanutils.DefaultBeanFactory.createBean(DefaultBeanFactory.java:116)
    at org.apache.commons.configuration2.beanutils.BeanHelper.createBean(BeanHelper.java:459)
    at org.apache.commons.configuration2.beanutils.BeanHelper.createBean(BeanHelper.java:479)
    at org.apache.commons.configuration2.beanutils.BeanHelper.createBean(BeanHelper.java:492)
    at org.apache.commons.configuration2.builder.BasicConfigurationBuilder.createResultInstance(BasicConfigurationBuilder.java:447)
    at org.apache.commons.configuration2.builder.BasicConfigurationBuilder.createResult(BasicConfigurationBuilder.java:417)
    at org.apache.commons.configuration2.builder.BasicConfigurationBuilder.getConfiguration(BasicConfigurationBuilder.java:285)
    at main.Main.main(Main.java:25)

我在这个链接中找到了关于此警告信息的说明。

- D.B.

---

我通过排除对commons-beanutils:1.9.2的传递依赖并添加对commons-beanutils:1.9.4的直接依赖，成功消除了警告信息。 - nzhenry

Answer 2

在Apache Commons Configuration中，有PropertiesConfiguration。它支持将分隔符字符串转换为数组/列表的功能。

例如，如果您有一个属性文件：

#Foo.properties
foo=bar1, bar2, bar3

使用以下代码：

PropertiesConfiguration config = new PropertiesConfiguration("Foo.properties");
String[] values = config.getStringArray("foo");

这将为您提供一个字符串数组["bar1", "bar2", "bar3"]

---

getString仅返回多值键的第一个值。尝试使用getStringArray以获取两个值。

完整代码示例：

ApacheCommonPropertyConfig.java

import java.util.List;

import org.apache.commons.configuration.ConfigurationException;
import org.apache.commons.configuration.PropertiesConfiguration;

public class ApacheCommonPropertyConfig {

    public static void main(String[] args) throws ConfigurationException {
        PropertiesConfiguration config;
        try {
            config = new PropertiesConfiguration("F://foo.properties");
            // For Array
            String[] values = config.getStringArray("foo");
            for(String strVal : values) {
                System.out.println("Array Value is: "+strVal);
            }
            // For List
            List<Object> linclude =  config.getList("foo");
            for(Object str : linclude){
                System.out.println("List Value is: "+str.toString());
            }
            // For List Another
            List<Object> list = config.getList("listOfValue", config.getList("foo"));
            for(Object str : list){
                System.out.println("Another List Value is: "+str.toString());
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

foo.properties

foo=bar1, bar2, bar3

输出：

Array Value is: bar1
Array Value is: bar2
Array Value is: bar3
List Value is: bar1
List Value is: bar2
List Value is: bar3
Another List Value is: bar1
Another List Value is: bar2
Another List Value is: bar3

---

另一个使用AbstractFileConfiguration的示例

ListDelimiterDemo.java

import org.apache.commons.configuration.AbstractFileConfiguration;
import org.apache.commons.configuration.ConfigurationException;
import org.apache.commons.configuration.PropertiesConfiguration;


public class ListDelimiterDemo {

    public static void main(String[] args) throws ConfigurationException {
        AbstractFileConfiguration config = new PropertiesConfiguration();
        config.setListDelimiter(',');
        config.load("F://foo.properties");

        for (Object listItem : config.getList("foo")) {
            System.out.println(listItem);
        }
    }
}

输出：

bar1
bar2
bar3

资源链接：

1. 从属性文件中读取列表并使用Spring注解@Value加载
2. PropertiesConfiguration类

- SkyWalker

---

谢谢您的回答和努力，+1。但问题是：如何使用apache.commons.configuration2来实现，而不是apache.commons.configuration。 - Sampada