JAVA操作properties文件 扯蛋版

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 */
package dataquery;
 
import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.Properties;
 
/**
 *
 * @author Administrator
 */
public class Properset{
 
    public static String readValue(String filePath, String key) {
        Properties props = new Properties();
        try {
            InputStream in = new BufferedInputStream(new FileInputStream(filePath));
            props.load(in);
            String value = props.getProperty(key);
            System.out.println(key + value);
            return value;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
 
    public static void writeProperties(String filePath, String parameterName, String parameterValue) {
        Properties prop = new Properties();
        try {
            InputStream fis = new FileInputStream(filePath);
            prop.load(fis);
            OutputStream fos = new FileOutputStream(filePath);
            prop.setProperty(parameterName, parameterValue);
            prop.store(fos, "Update '" + parameterName + "' value");
        } catch (IOException e) {
            System.err.println("Visit " + filePath + " for updating " + parameterName + " value error");
        }
    }
}