如何用io写文件追加内容？
public static void setInfoByProperty(String id,String property,String propertyValue) throws Exception{
File file = getFile(id);
PrintWriter pw = new PrintWriter(file);
Properties ps = new Properties();
ps.setProperty(property,propertyValue);
ps.list(pw);
pw.flush();
pw.close();
}
Properties pro = new Properties();
pro.load(new FileInputStream("readxmllasttime.porperties"));
for (Enumeration e = pro.propertyNames(); e.hasMoreElements();) {
String s = (String) e.nextElement(); // 遍历所有元素
if (s.equals(key)) {
/**如果键相同则覆盖*/
pro.setProperty(key, maxdate.getTime() + "");
} else {
/**否则就原样写入*/
pro.setProperty(s, pro.getProperty(s));
}
}
pro.store(new FileOutputStream("readxmllasttime.porperties"),"描述信息");
File file = getFile(id);
FileInputStream fis = new FileInputStream(file);
Properties ps = new Properties();
ps.load(fis);
ps.setProperty(property,propertyValue);
FileOutputStream fos = new FileOutputStream(file);
ps.store(fos, "");
os.close();
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import java.util.Properties;
/**
* 属性文件读写工具
* @author shanl
*
*/
public class ResourceUtil {
private File configFile = null;
private Properties prop = null;
public ResourceUtil(URL url){
load(url);
}
/**
* 从classpath下查找指定资源<br/>
* 以类的部署目录为根，
* 例:conf/config.properties
* @param res
* @return
*/
public static ResourceUtil getInstanceByClasspath(String res){
URL url = ClassLoader.getSystemResource(res);
return new ResourceUtil(url);
}
/**
* 从classload下查找指定资源<br/>
* 以类的部署目录为根，
* 例:conf/config.properties
* @param res
* @return
*/
public static ResourceUtil getInstanceByClassloader(String res){
URL url = ResourceUtil.class.getClassLoader().getResource(res);
return new ResourceUtil(url);
}
/**
* 从配置文件中加载
* @param url
*/
private void load(URL url){
InputStream in = null;
try{
prop = new Properties();
configFile = new File(url.toURI());
in = new FileInputStream(configFile);
prop.load(in);
}catch(Exception ex){
throw new RuntimeException(ex);
}finally{
try{
if(null!=in) in.close();
}catch(Exception ex){
}
}
}
/**
* 返回某一项属性值
* @param key
* @return 返回属性值,如果不存在或没有值则返回""
*/
public String getProperty(String key){
return prop.getProperty(key,"");
}
/**
* 设置一项属性值
* @param key
* @param value
*/
public void setProperty(String key, String value){
prop.setProperty(key, value);
}
/**
* 移除一项
* @param key
*/
public void removeProperty(String key){
prop.remove(key);
}
/**
* 将当前各属性值保存至文件
*/
public void store(){
OutputStream out = null;
try{
out = new FileOutputStream(configFile);
prop.store(out, null);
}catch(Exception ex){
throw new RuntimeException(ex);
}finally{
try{
if(null!=out) out.close();
}catch(Exception ex){
}
}
}
}
BufferedWriter writer = null;
try {
writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(bunles,true)));
writer.write(“xxxx追加的内容”));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
if(writer != null)
writer.close();
}
public static void setInfoByProperty(String id,String property,String propertyValue) throws Exception{
File file = getFile(id);
//PrintWriter pw = new PrintWriter(file);
Properties ps = new Properties();
ps.load(new FileReader(file));
for (Enumeration e = ps.propertyNames(); e.hasMoreElements();) {
String s = (String) e.nextElement(); // 遍历所有元素
if (s.equals(property)) {/**如果键相同则覆盖*/
//ps.setProperty(property,propertyValue);
} else {/**否则就原样写入*/
ps.setProperty(property,propertyValue);
}
}
ps.store(new FileWriter(file),"qqq");
}
