1. 怎麼用java備份mysql資料庫
首先，設置mysql的環境變數（在path中添加%MYSQL_HOME%\bin），重啟電腦。
完整代碼：
備份：
public static void main(String[] args) {
backup();
load();
}
public static void backup() {
try {
Runtime rt = Runtime.getRuntime();
// 調用 mysql 的 cmd:
Process child = rt
.exec("mysqlmp -u root --set-charset=utf8 bjse act_obj");// 設置導出編碼為utf8。這里必須是utf8
// 把進程執行中的控制台輸出信息寫入.sql文件，即生成了備份文件。註：如果不對控制台信息進行讀出，則會導致進程堵塞無法運行
InputStream in = child.getInputStream();// 控制台的輸出信息作為輸入流
InputStreamReader xx = new InputStreamReader(in, "utf8");// 設置輸出流編碼為utf8。這里必須是utf8，否則從流中讀入的是亂碼
String inStr;
StringBuffer sb = new StringBuffer("");
String outStr;
// 組合控制台輸出信息字元串
BufferedReader br = new BufferedReader(xx);
while ((inStr = br.readLine()) != null) {
sb.append(inStr + "\r\n");
}
outStr = sb.toString();
// 要用來做導入用的sql目標文件：
FileOutputStream fout = new FileOutputStream(
"e:/mysql-5.0.27-win32/bin/bjse22.sql");
OutputStreamWriter writer = new OutputStreamWriter(fout, "utf8");
writer.write(outStr);
// 註：這里如果用緩沖方式寫入文件的話，會導致中文亂碼，用flush()方法則可以避免
writer.flush();
// 別忘記關閉輸入輸出流
in.close();
xx.close();
br.close();
writer.close();
fout.close();
System.out.println("");
} catch (Exception e) {
e.printStackTrace();
}
}
public static void load() {
try {
String fPath = "e:/mysql-5.0.27-win32/bin/bjse22.sql";
Runtime rt = Runtime.getRuntime();
// 調用 mysql 的 cmd:
Process child = rt.exec("mysql -u root bjse ");
OutputStream out = child.getOutputStream();//控制台的輸入信息作為輸出流
String inStr;
StringBuffer sb = new StringBuffer("");
String outStr;
BufferedReader br = new BufferedReader(new InputStreamReader(
new FileInputStream(fPath), "utf8"));
while ((inStr = br.readLine()) != null) {
sb.append(inStr + "\r\n");
}
outStr = sb.toString();
OutputStreamWriter writer = new OutputStreamWriter(out, "utf8");
writer.write(outStr);
// 註：這里如果用緩沖方式寫入文件的話，會導致中文亂碼，用flush()方法則可以避免
writer.flush();
// 別忘記關閉輸入輸出流
out.close();
br.close();
writer.close();
System.out.println("");
} catch (Exception e) {
e.printStackTrace();
}
}
備份語句：
mysql> SELECT * INTO OUTFILE "D:\\data\\db_testtemp.txt" fields terminated by ',
' from db_testtemp where std_state='1';
Query OK, 1 row affected (0.00 sec)
mysql> SELECT * INTO OUTFILE "D:\\data\\db_testtemp.txt" fields terminated by ',
' from db_testtemp ;
Query OK, 2 rows affected (0.00 sec)
只生成一個只有數據的.txt:SELECT * INTO OUTFILE "D:\\data\\db_testtemp.txt" fields terminated by ',' lines terminated by '\r\n' from db_testtemp ;
只生成一個只有數據的.txt:mysqlmp -uroot -pncae2010 -w "std_state='1'" -T D:\data --no-create-info --fields-terminated-by=, exam db_testtemp
生成一個創建資料庫語句的.sql,一個只有數據的.txt:mysqlmp -uroot -pncae2010 -w "std_state='1'" -T D:\data --fields-terminated-by=, exam db_testtemp
只生成insert語句：mysqlmp -uroot -pncae2010 -w "std_state='1'" -t exam db_testtemp > D:\data\a.sql
2. java怎麼獲得 mysql 當前資料庫大小
我倒是有個方法，以前我做個mysql資料庫備份，備份的時候也就是賦值資料庫的過程，當然能知道大小了，要是想實時獲取的話那就就定義一個線程來空值就可以了，代碼大概如下：其中賦值的過程樓主可省略，你要的就是一個值，就是sb的大小。。
package com.huagong.backdatabase;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
public class BackmysqlUtil {
/**
*
* mysql數據備份 接收腳本名，並返回此路徑
*
* sql為備份的腳本名比如eg.sql
* @throws IOException
*
*/
public static void backup(String sqlname,String readlyPath) throws IOException {
Properties pros = getPprVue("backup.properties");
String username = pros.getProperty("username");
String password = pros.getProperty("password");
// 得到MYSQL的用戶名密碼後調用 mysql 的 cmd:
String databaseName = pros.getProperty("databaseName");
String address = pros.getProperty("address");
File backupath = new File(readlyPath);
if (!backupath.exists()) {
backupath.mkdir();
}
StringBuffer sb = new StringBuffer();
sb.append(" mysqlmp ");
sb.append("--opt ");
sb.append("-h ");
sb.append(address);
sb.append(" ");
sb.append("--user=");
sb.append(username);
sb.append(" ");
sb.append("--password=");
sb.append(password);
sb.append(" ");
sb.append("--lock-all-tables=true ");
sb.append("--result-file=");
sb.append(readlyPath);
sb.append(sqlname);
sb.append(" ");
sb.append("--default-character-set=utf8 ");
sb.append(databaseName);
Runtime cmd = Runtime.getRuntime();
Process p = cmd.exec(sb.toString());
pros.setProperty("ss", "ss");
}
public static void load(String filename,String readlyPath) throws IOException {
Properties pros = getPprVue("backup.properties");
// 這里是讀取的屬性文件，也可以直接使用
String root = pros.getProperty("username");
String pass = pros.getProperty("password");
// 得到MYSQL的用戶名密碼後調用 mysql 的 cmd:
String filepath = readlyPath + filename; // 備份的路徑地址
// 新建資料庫newdb
String stmt1 = "mysqladmin -u " + root + " -p" + pass
+ " create newdb";
// -p後面加的是你的密碼
String stmt2 = "mysql -u " + root + " -p" + pass + " newdb < "
+ filepath;
String[] cmd = { "cmd", "/c", stmt2 };
Runtime.getRuntime().exec(stmt1);
Runtime.getRuntime().exec(cmd);
System.out.println("數據已從 " + filepath + " 導入到資料庫中");
}
// 載入配置文件
public static Properties getPprVue(String properName) throws IOException {
InputStream inputStream = BackmysqlUtil.class.getClassLoader()
.getResourceAsStream(properName);
Properties p = new Properties();
p.load(inputStream);
inputStream.close();
return p;
}
//測試
public static void main(String[] args) throws IOException {
backup("eg.sql","e:\\mysql\\");
//load("eg.sql","e:\\mysql\\");
}
}
配置文件：
backup.properties配置文件的內容如下,用戶名和密碼隨便你改。
#mysqlpath = D:\\ProgramFiles\\wamp\\bin\\mysql\\mysql5.1.32\\bin
#sqlpath = E:\\MySQl\\
username = root
password = cool
address=localhost
databaseName=huagongdb
最後你想什麼時候調用直接就在程序里用一個線程式控制制調用就可以了。