java中的properties檔案是一種配置檔案，主要用于表達配置資訊，檔案類型為*.properties，格式為文本檔案，檔案的内容是格式是”鍵=值”的格式，在properties
檔案中，可以用”#”來作注釋，properties檔案在Java程式設計中用到的地方很多，操作很友善。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;
public PropertiesUtil(String fileName) {
this.fileName = fileName;
File file = new File(fileName);
try {
in = new FileInputStream(file);
p = new Properties();
// 載入檔案
p.load(in);
in.close();
} catch (FileNotFoundException e) {
System.err.println("配置檔案config.properties找不到！！");
e.printStackTrace();
} catch (Exception e) {
System.err.println("讀取配置檔案config.properties錯誤！！");
e.printStackTrace();
}
}
public static String getConfigFile(HttpServlet hs) {
return getConfigFile(hs, "config.properties");
}
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;
}
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;
}
public void list() {
p.list(System.out);
}
public String getValue(String itemName) {
return p.getProperty(itemName);
}
public String getValue(String itemName, String defaultValue) {
return p.getProperty(itemName, defaultValue);
}
public void setValue(String itemName, String value) {
p.setProperty(itemName, value);
return;
}
public void saveFile(String fileName, String description) throws Exception {
try {
File f = new File(fileName);
out = new FileOutputStream(f);
p.store(out, description);// 儲存檔案
out.close();
} catch (IOException ex) {
throw new Exception("無法儲存指定的配置檔案:" + fileName);
}
}
public void saveFile(String fileName) throws Exception {
saveFile(fileName, "");
}
public void saveFile() throws Exception {
if (fileName.length() == 0)
throw new Exception("需指定儲存的配置檔案名");
saveFile(fileName);
}
public void deleteValue(String value) {
p.remove(value);
}
public static void main(String[] args) {
String file = "D:\\ttt.properties";
PropertiesUtil pu = new PropertiesUtil(file);
pu.list();
}
}