package com.adrop.util; import java.io.*; import java.util.properties; import javax.servlet.http.*; import javax.servlet.*; import javax.servlet.jsp.*; public class propertiesutil { private string filename; private properties p; private fileinputstream in; private fileoutputstream out; /** * 根据传进的文件名载入文件 * @param filename string */ public propertiesutil(string filename) { this.filename=filename; file file = new file(filename); try { in = new fileinputstream(file); p = new properties(); //载入文件 p.load(in); in.close(); } catch (filenotfoundexception e) { system.err.println("设置文件config.properties未找到！！"); e.printstacktrace(); } catch (exception e) { system.err.println("读取设置文件config.properties错误！！"); e.printstacktrace(); } } /** * 设置文件一律为config.propertities，并且统一放在web应用的根目录下。 * @return string */ public static string getconfigfile(httpservlet hs) { return getconfigfile(hs,"config.properties"); } /** * 在servlet中使用,直接用this作为参数,httpservlet类型 * 根据设置文件名从当前web应用的根目录下找出设置文件 * @param hs httpservlet * @param configfilename string设置文件名字 * @return string */ public static string getconfigfile(httpservlet hs, string configfilename) { string configfile = ""; servletcontext sc = hs.getservletcontext(); configfile = sc.getrealpath("/" + configfilename); if (configfile == null || configfile.equals("")) { configfile = "/" + configfilename; } return configfile; } /** * jsp中用pagecontext作参数 * @param hs pagecontext * @param configfilename string 设置文件名字 * @return string */ public static string getconfigfile(pagecontext hs, string configfilename) { string configfile = ""; servletcontext sc = hs.getservletcontext(); configfile = sc.getrealpath("/" + configfilename); if (configfile == null || configfile.equals("")) { configfile = "/" + configfilename; } return configfile; } /** * 列出所有的设置文件内容 */ public void list() { p.list(system.out); } /** * 指定设置项名称，返回设置值 * @param itemname string * @return string */ public string getvalue(string itemname){ return p.getproperty(itemname); } /** * 指定设置项名称和默认值，返回设置值 * @param itemname string * @param defaultvalue string * @return string */ public string getvalue(string itemname, string defaultvalue){ return p.getproperty(itemname,defaultvalue); } /** * 设置设置项名称及其值 * @param itemname string * @param value string */ public void setvalue(string itemname,string value){ p.setproperty(itemname,value); return; } /** * 保存设置文件，指定文件名和抬头描述 * @param filename string * @param description string * @throws exception */ public void savefile(string filename,string description)throws exception{ try { file f=new file(filename); out = new fileoutputstream(f); p.store(out, description);//保存文件 out.close(); } catch (ioexception ex) { throw new exception ("无法保存指定的设置文件:"+filename); } } /** * 保存设置文件，指定文件名 * @param filename string * @throws exception */ public void savefile(string filename) throws exception { savefile(filename,""); } /** * 保存设置文件，采用原文件名 * @throws exception */ public void savefile() throws exception { if(filename.length()==0) throw new exception ("需指定保存的设置文件名"); savefile(filename); } /** * 删除一个属性 * @param value string */ public void deletevalue(string value){ p.remove(value); } /** * main method for test * @param args string[] */ public static void main(string[] args) { string file = "f:＼＼p.properties"; propertiesutil pu = new propertiesutil(file); pu.list(); } }
一个既能读又写入dbConfig.properties（数据库配置文件）java源代码
答案一
public class ConnectionHelper {/*** 通过JNDI获取数据源*/private static DataSource getDataSource(){//建立JNDI的上下文try {InitialContext ct = new InitialContext();DataSource source = (DataSource)ct.lookup("java:/comp/env/jdbc/shop");return source;} catch (Exception e) {throw new RuntimeException("获取数据源失败",e);}}//从Properties文件加载配置参数public static Properties getConfig(){Properties pro = new Properties();InputStream is = ConnectionHelper.class.getResourceAsStream("/com/lxw/config/db.properties");try {pro.load(is);return pro;} catch (IOException e) {throw new DBException("加载配置文件失败",e);}}private static DataSource ds = null;//自构建数据源public static synchronized DataSource getMyDataSource(){if(ds == null){Properties pro = getConfig();BasicDataSource bdc = new BasicDataSource();bdc.setDriverClassName(pro.getProperty("dbDriver"));bdc.setUrl(pro.getProperty("dbUrl"));bdc.setUsername(pro.getProperty("dbUser"));bdc.setPassword(pro.getProperty("dbPassword"));String num = pro.getProperty("dbMaxActive");if(num != null && num.equals("")){bdc.setMaxActive(Integer.parseInt(num));}/*bdc.setDriverClassName("com.mysql.jdbc.Driver");bdc.setUrl("jdbc:mysql://localhost:3306/shop");bdc.setUsername("root");bdc.setPassword("123");bdc.setMaxActive(20);*/ds = bdc;}return ds;}
//获取统一的数据库连接public static Connection getCon(){try {//return getDataSource().getConnection();//通过自构建的数据源获取连接return getMyDataSource().getConnection();} catch (SQLException e) {throw new DBException("获取数据库连接失败",e);}}//关闭连接public static void closeCon(Connection con){try {if(null != con && !con.isClosed()){con.close();con = null;}} catch (SQLException e) {throw new DBException("关闭数据库连接失败",e);}}public static void main(String[] args) {System.out.println(getCon());System.out.println("获取连接成功");}}
答案二
/*** 读取属性文件* <p>Title: </p>* <p>Description: </p>* <p>Copyright: Copyright (c) 2005</p>* <p>Company: </p>* @author zhanggy* @version 1.0*/public class PropertyManager {
private static PropertyManager manager = null;private static Object managerLock = new Object();
/*** Returns a Jive property.** @param name the name of the property to return.* @return the property value specified by name.*/public static String getProperty(String propsName,String name) {if (manager == null) {synchronized(managerLock) {if (manager == null) {manager = new PropertyManager(propsName);}}}return manager.getProp(name);}
private Properties properties = null;private Object propertiesLock = new Object();private String resourceURI;
/*** Creates a new PropertyManager. Singleton access only.*/private PropertyManager(String resourceURI) {this.resourceURI = resourceURI;}
/*** Gets a Jive property. Jive properties are stored in jive.properties.* The properties file should be accesible from the classpath. Additionally,* it should have a path field that gives the full path to where the* file is located. Getting properties is a fast operation.** @param name the name of the property to get.* @return the property specified by name.*/protected String getProp(String name) {//If properties aren't loaded yet. We also need to make this thread//safe, so synchronize...if (properties == null) {synchronized(propertiesLock) {//Need an additional checkif (properties == null) {loadProps();}}}String property = properties.getProperty(name);if (property == null) {return null;}else {return property.trim();}}
/*** Loads Jive properties from the disk.*/private void loadProps() {properties = new Properties();InputStream in = null;try {in = getClass().getResourceAsStream(resourceURI);properties.load(in);in.close();}catch (Exception e) {System.err.println("Error reading properties in PropertyManager.loadProps() " + e);e.printStackTrace();}finally {try {in.close();} catch (Exception e) { }}}
// public static void main(String[] args) {// String dbtype = PropertyManager.getProperty("/dbconfig.properties", "dbtype");// System.out.println("dbtype = "+dbtype);// }}
java获取properties配置文件
package test.bwl; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.util.Properties; public class Test { private static Properties properties = new Properties(); public static void main(String[] args) { try { InputStream is = Test.class.getClassLoader().getResourceAsStream("cache.properties"); properties.load(is); String size = properties.getProperty("cache.size"); writeLog("配置成功！" + size); } catch (FileNotFoundException e) { writeLog("配置文件不存在！" + e.getMessage()); } catch (IOException e) { writeLog("读取配置文件IO错误！" + e.getMessage()); } } public static void writeLog(String strLog) { System.out.println(strLog); } } package test.bwl;
import java.io.FileNotFoundException;import java.io.IOException;import java.io.InputStream;import java.util.Properties;
public class Test {private static Properties properties = new Properties();
public static void main(String[] args) {try {InputStream is = Test.class.getClassLoader().getResourceAsStream("cache.properties");properties.load(is);String size = properties.getProperty("cache.size");writeLog("配置成功！" + size);} catch (FileNotFoundException e) {writeLog("配置文件不存在！" + e.getMessage());} catch (IOException e) {writeLog("读取配置文件IO错误！" + e.getMessage());}}
public static void writeLog(String strLog) {System.out.println(strLog);}}
package test.bwl; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FilenameFilter; import java.io.IOException; import java.io.InputStream; import java.util.Collections; import java.util.HashMap; import java.util.Map; import java.util.Properties; import java.util.regex.Pattern; /** * 配置信息管理器 * * @author bwl * @version 1.0 */ public class ConfigManager { /** * 提供单例对象的静态内部类 */ private static class SingletonHolder { public static ConfigManager instance = new ConfigManager(); } /** * 获取对象实例 * @return */ public static ConfigManager getInstance() { return SingletonHolder.instance; } /** * 存储问题列表的Map */ private Map<String, Properties> name2properties; /** * 构造方法，请使用getInstance()获取实例 */ private ConfigManager() { name2properties = Collections.synchronizedMap(new HashMap<String, Properties>()); doInit(); } /** * 初始化方法 */ private void doInit() { try { File path = new File("./conf/"); if (!path.exists()) { System.out.println("ConfilgManager Init Error: There is no folder named 'conf' under src file."); return; } File[] confFiles = path.listFiles(new DirFilter(".*//.properties")); for (int i = 0; i < confFiles.length; i++) { File f = confFiles[i]; if (f.exists() && f.isFile()) { Properties properties = new Properties(); InputStream is = new FileInputStream(f); properties.load(is); name2properties.put(f.getName(), properties); } } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } /** * 获取配置项的值 * @param fileName 配置文件的名称 * @param key 关键码的值 * @return 配置项 */ public String getProperty(String fileName, String key) { if (fileName == null || fileName.length() == 0) { return null; } Properties prop = name2properties.get(fileName); if (prop != null) { return prop.getProperty(key); } return null; } /** * 获取整形的配置项的值 * @param fileName 配置文件的名称 * @param keyName 关键码的值 * @return 如果正确则返回数字，否则返回-1 */ public int getIntProperty(String fileName, String key) { String value = this.getProperty(fileName, key); int result = -1; if (value == null) { return result; } try { result = Integer.parseInt(value); return result; } catch (Exception e) { //Do nothing } return result; } /** * 过滤属性文件的内部类 */ class DirFilter implements FilenameFilter { /** * 记录文件名格式的正则对象 */ private Pattern pattern; public DirFilter(String regex) { pattern = Pattern.compile(regex); } public boolean accept(File dir, String name) { return pattern.matcher(new File(name).getName()).matches(); } } public static void main(String[] args) { ConfigManager config = ConfigManager.getInstance(); System.out.println(config.getIntProperty("cache.properties", "cache.size") + ""); System.out.println(config.getProperty("javagroups.properties", "bus_name") + ""); }
