java.lang.IllegalArgumentException:'hello'不包含等号

Question

我目前正在使用Apache commons配置库来编写和读取文件中的数据.我能够将键值对colors = hello保存到user..properties文件中,但是当我尝试读取该值时,获取以下异常.

Exception in thread "main" java.lang.IllegalArgumentException: 'hello' does not contain an equals sign
at org.apache.commons.configuration.AbstractConfiguration.getProperties(AbstractConfiguration.java:625)
at org.apache.commons.configuration.AbstractConfiguration.getProperties(AbstractConfiguration.java:579)
at com.code.prep.CommonsMain.readProperties(CommonsMain.java:21)
at com.code.prep.CommonsMain.main(CommonsMain.java:12)

代码如下

package com.code.prep;

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

public class CommonsMain {

    public static void main(String[] args) {

        CommonsMain main = new CommonsMain();
        main.readProperties();
//      main.writeProperties();
    }

    public void readProperties(){

        PropertiesConfiguration config = new PropertiesConfiguration();
        try {
            config.load("user.properties");
            System.out.println(config.getProperties("colors"));
        } catch (ConfigurationException e) {
            e.printStackTrace();
        }
    }

    public void writeProperties(){
        PropertiesConfiguration config = new PropertiesConfiguration();
        try {
            config.load("user.properties");
            config.setProperty("colors", "hello");
            config.save("user.properties");
        } catch (ConfigurationException e) {
            e.printStackTrace();
        }
    }
}

类路径中的Jars是:

commons-configuration-1.9.jar commons-lang-2.4.jar commons-logging-1.1.1.jar

user.properties包含

colors = hello user = thejavamonk

Answer 1

你不应该使用

config.getProperties("colors")

但

config.getProperty("colors")

"getProperties(code)"正在查找表单的user.properties文件中的(多个)行:

code key=val

所以它期待你的代码,因为它具有如下行:

colors foreground=black
colors background=white

等等