Properties类应用详解
1、获取JVM的系统属性
import java.util.Properties;
public class ReadJVM {
public static void main(String[] args) {
Properties pps = System.getProperties();
pps.list(System.out);
}
}
2、随便新建一个配置文件(Test.properties)
name=JJ
Weight=4444
Height=3333
public class getProperties {
public static void main(String[] args) throws FileNotFoundException, IOException {
Properties pps = new Properties();
pps.load(new FileInputStream("Test.properties"));
Enumeration enum1 = pps.propertyNames();//得到配置文件的名字
while(enum1.hasMoreElements()) {
String strKey = (String) enum1.nextElement();
String strValue = pps.getProperty(strKey);
System.out.println(strKey + "=" + strValue);
}
}
}
3、一个比较综合的实例
public class TestProperties {
//根据Key读取Value
public static String GetValueByKey(String filePath, String key) {
Properties pps = new Properties();
try {
InputStream in = new BufferedInputStream (new FileInputStream(filePath));
pps.load(in);
String value = pps.getProperty(key);
System.out.println(key + " = " + value);
return value;
}catch (IOException e) {
e.printStackTrace();
return null;
}
}
//读取Properties的全部信息
public static void GetAllProperties(String filePath) throws IOException {
Properties pps = new Properties();
InputStream in = new BufferedInputStream(new FileInputStream(filePath));
pps.load(in);
Enumeration en = pps.propertyNames(); //得到配置文件的名字
while(en.hasMoreElements()) {
String strKey = (String) en.nextElement();
String strValue = pps.getProperty(strKey);
System.out.println(strKey + "=" + strValue);
}
}
//写入Properties信息
public static void WriteProperties (String filePath, String pKey, String pValue) throws IOException {
Properties pps = new Properties();
InputStream in = new FileInputStream(filePath);
pps.load(in);
OutputStream out = new FileOutputStream(filePath);
pps.setProperty(pKey, pValue);
pps.store(out, "Update " + pKey + " name");
}
public static void main(String [] args) throws IOException{
//String value = GetValueByKey("Test.properties", "name");
//System.out.println(value);
//GetAllProperties("Test.properties");
WriteProperties("Test.properties","long", "212");
}
}
结果：
Test.properties中文件的数据为：
#Update long name
#Sun Feb 23 18:17:16 CST 2014
name=JJ
Weight=4444
long=212
Height=3333
了解更多关于软件方面的知识，请访问上海软件培训学校
