下面是遍历属性的另一种方法:

Enumeration eProps = properties.propertyNames();
while (eProps.hasMoreElements()) { 
    String key = (String) eProps.nextElement(); 
    String value = properties.getProperty(key); 
    System.out.println(key + " => " + value); 
}

You can store the file anywhere you like. If you want to keep it in your jar file, you'll want to use Class.getResourceAsStream() or ClassLoader.getResourceAsStream() to access it. If it's on the file system it's slightly easier. Any extension is fine, although .properties is more common in my experience Load the file using Properties.load, passing in an InputStream or a StreamReader if you're using Java 6. (If you are using Java 6, I'd probably use UTF-8 and a Reader instead of the default ISO-8859-1 encoding for a stream.) Iterate through it as you'd iterate through a normal Hashtable (which Properties derives from), e.g. using keySet(). Alternatively, you can use the enumeration returned by propertyNames().

读取属性文件并将其内容加载到properties

String filename = "sample.properties";
Properties properties = new Properties();

input = this.getClass().getClassLoader().getResourceAsStream(filename);
properties.load(input);

下面是遍历Properties的有效方法

    for (Entry<Object, Object> entry : properties.entrySet()) {

        System.out.println(entry.getKey() + " => " + entry.getValue());
    }

这里是就绪静态类

import java.io.*;
import java.util.Properties;
public class Settings {
    public static String Get(String name,String defVal){
        File configFile = new File(Variables.SETTINGS_FILE);
        try {
            FileReader reader = new FileReader(configFile);
            Properties props = new Properties();
            props.load(reader);
            reader.close();
            return props.getProperty(name);
        } catch (FileNotFoundException ex) {
            // file does not exist
            logger.error(ex);
            return defVal;
        } catch (IOException ex) {
            // I/O error
            logger.error(ex);
            return defVal;
        } catch (Exception ex){
            logger.error(ex);
            return defVal;
        }
    }
    public static Integer Get(String name,Integer defVal){
        File configFile = new File(Variables.SETTINGS_FILE);
        try {
            FileReader reader = new FileReader(configFile);
            Properties props = new Properties();
            props.load(reader);
            reader.close();
            return Integer.valueOf(props.getProperty(name));
        } catch (FileNotFoundException ex) {
            // file does not exist
            logger.error(ex);
            return defVal;
        } catch (IOException ex) {
            // I/O error
            logger.error(ex);
            return defVal;
        } catch (Exception ex){
            logger.error(ex);
            return defVal;
        }
    }
    public static Boolean Get(String name,Boolean defVal){
        File configFile = new File(Variables.SETTINGS_FILE);
        try {
            FileReader reader = new FileReader(configFile);
            Properties props = new Properties();
            props.load(reader);
            reader.close();
            return Boolean.valueOf(props.getProperty(name));
        } catch (FileNotFoundException ex) {
            // file does not exist
            logger.error(ex);
            return defVal;
        } catch (IOException ex) {
            // I/O error
            logger.error(ex);
            return defVal;
        } catch (Exception ex){
            logger.error(ex);
            return defVal;
        }
    }
    public static void Set(String name, String value){
        File configFile = new File(Variables.SETTINGS_FILE);
        try {
            Properties props = new Properties();
            FileReader reader = new FileReader(configFile);
            props.load(reader);
            props.setProperty(name, value.toString());
            FileWriter writer = new FileWriter(configFile);
            props.store(writer, Variables.SETTINGS_COMMENT);
            writer.close();
        } catch (FileNotFoundException ex) {
            // file does not exist
            logger.error(ex);
        } catch (IOException ex) {
            // I/O error
            logger.error(ex);
        } catch (Exception ex){
            logger.error(ex);
        }
    }
    public static void Set(String name, Integer value){
        File configFile = new File(Variables.SETTINGS_FILE);
        try {
            Properties props = new Properties();
            FileReader reader = new FileReader(configFile);
            props.load(reader);
            props.setProperty(name, value.toString());
            FileWriter writer = new FileWriter(configFile);
            props.store(writer,Variables.SETTINGS_COMMENT);
            writer.close();
        } catch (FileNotFoundException ex) {
            // file does not exist
            logger.error(ex);
        } catch (IOException ex) {
            // I/O error
            logger.error(ex);
        } catch (Exception ex){
            logger.error(ex);
        }
    }
    public static void Set(String name, Boolean value){
        File configFile = new File(Variables.SETTINGS_FILE);
        try {
            Properties props = new Properties();
            FileReader reader = new FileReader(configFile);
            props.load(reader);
            props.setProperty(name, value.toString());
            FileWriter writer = new FileWriter(configFile);
            props.store(writer,Variables.SETTINGS_COMMENT);
            writer.close();
        } catch (FileNotFoundException ex) {
            // file does not exist
            logger.error(ex);
        } catch (IOException ex) {
            // I/O error
            logger.error(ex);
        } catch (Exception ex){
            logger.error(ex);
        }
    }
}

以下示例:

Settings.Set("valueName1","value");
String val1=Settings.Get("valueName1","value");
Settings.Set("valueName2",true);
Boolean val2=Settings.Get("valueName2",true);
Settings.Set("valueName3",100);
Integer val3=Settings.Get("valueName3",100);

在顺序:

您可以将文件存储在几乎任何地方。 不需要延期。 Montecristo已经说明了如何加载这个。这应该没问题。 propertyNames()提供了一个用于迭代的枚举。

属性已经成为遗产。首选项类优先于属性。

偏好数据的层次集合中的一个节点。这个类允许应用程序存储和检索用户和系统首选项以及配置数据。此数据持久地存储在依赖于实现的后备存储区中。典型的实现包括平面文件、特定于操作系统的注册表、目录服务器和SQL数据库。该类的用户不需要关心后台存储的细节。

与基于字符串的键值对的属性不同，Preferences类有几个方法用于在Preferences数据存储中获取和放置基本数据。我们只能使用以下类型的数据:

字符串 布尔 双 浮动 int 长 字节数组

要加载属性文件，可以提供绝对路径，如果属性文件在类路径中，则使用getResourceAsStream()。

package com.mypack.test;

import java.io.*;
import java.util.*;
import java.util.prefs.Preferences;

public class PreferencesExample {

    public static void main(String args[]) throws FileNotFoundException {
        Preferences ps = Preferences.userNodeForPackage(PreferencesExample.class);
        // Load file object
        File fileObj = new File("d:\\data.xml");
        try {
            FileInputStream fis = new FileInputStream(fileObj);
            ps.importPreferences(fis);
            System.out.println("Prefereces:"+ps);
            System.out.println("Get property1:"+ps.getInt("property1",10));

        } catch (Exception err) {
            err.printStackTrace();
        }
    }
}

xml文件:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE preferences SYSTEM 'http://java.sun.com/dtd/preferences.dtd'>
<preferences EXTERNAL_XML_VERSION="1.0">
<root type="user">
<map />
<node name="com">
  <map />
  <node name="mypack">
    <map />
    <node name="test">
      <map>
        <entry key="property1" value="80" />
        <entry key="property2" value="Red" />
      </map>
    </node>
  </node>
</node>
</root>
</preferences>

看看这篇关于偏好商店内部的文章