![](/img/trans.png)
[英]mysqldump.exe is creating blank mysql database backup file when mysqldump exe is invoked through java
[英]Error occurs when restoring a backup file created with mysqldump in Java
我有一個Swing應用程序,允許用戶備份或恢復數據庫。 對於備份,沒問題。
對於導入,當在mysql命令行中完成時,一切正常,例如C:\\ Users \\ Admin71> mysql -u root -p philateliodb <C:\\ Export_DB_Philatelio_18_09_2014_12_39_34.sql
但是當嘗試從Java代碼中導入時,它不起作用。 這是我使用的代碼:
try
{
File file = fileChooser.getSelectedFile();
//DISABLE FOREIGN KEY CHECKS FOR IMPORT
Connection con = Share.connection;
Statement stmt = con.createStatement();
stmt.execute("SET FOREIGN_KEY_CHECKS=0");
stmt.close();
//////////
String dbUserName = "root";
String dbPassword = "";
String dbName = "philateliodb";
String executeCmd = "mysql -u " + dbUserName + " -p" + dbPassword + " " + dbName + " <" + "\""
+ file.getCanonicalPath() + "\"";
Process runtimeProcess = Runtime.getRuntime().exec(executeCmd);
InputStream is = runtimeProcess.getInputStream();
int byteRead = -1;
while ( (byteRead = is.read()) != -1 )
{
System.out.print((char) byteRead);
}
int processComplete = runtimeProcess.waitFor();
if ( processComplete == 0 )
{
System.out.println("The database has been restored !");
}
else
{
System.out.println("Error : the database could not be restored !");
}
//RE_ENABLE FOREIGN KEY CHECKS AFTER IMPORT
stmt = con.createStatement();
stmt.execute("SET FOREIGN_KEY_CHECKS=1");
stmt.close();
//////////
}
catch (IOException e)
{
e.printStackTrace();
}
catch (SQLException e)
{
e.printStackTrace();
}
catch (InterruptedException e)
{
e.printStackTrace();
}
但我總是得到“錯誤:數據庫無法恢復!” 信息。
這也是我從Eclipse中的控制台輸出得到的:
mysql Ver 14.14 Distrib 5.6.17, for Win64 (x86_64)
Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Usage: mysql [OPTIONS] [database]
-?, --help Display this help and exit.
-I, --help Synonym for -?
--auto-rehash Enable automatic rehashing. One doesn't need to use
'rehash' to get table and field completion, but startup
and reconnecting may take a longer time. Disable with
--disable-auto-rehash.
(Defaults to on; use --skip-auto-rehash to disable.)
-A, --no-auto-rehash
No automatic rehashing. One has to use 'rehash' to get
table and field completion. This gives a quicker start of
mysql and disables rehashing on reconnect.
--auto-vertical-output
Automatically switch to vertical output mode if the
result is wider than the terminal width.
-B, --batch Don't use history file. Disable interactive behavior.
(Enables --silent.)
--bind-address=name IP address to bind to.
--character-sets-dir=name
Directory for character set files.
--column-type-info Display column type information.
-c, --comments Preserve comments. Send comments to the server. The
default is --skip-comments (discard comments), enable
with --comments.
-C, --compress Use compression in server/client protocol.
-#, --debug[=#] This is a non-debug version. Catch this and exit.
--debug-check Check memory and open file usage at exit.
-T, --debug-info Print some debug info at exit.
-D, --database=name Database to use.
--default-character-set=name
Set the default character set.
--delimiter=name Delimiter to be used.
--enable-cleartext-plugin
Enable/disable the clear text authentication plugin.
-e, --execute=name Execute command and quit. (Disables --force and history
file.)
-E, --vertical Print the output of a query (rows) vertically.
-f, --force Continue even if we get an SQL error.
-G, --named-commands
Enable named commands. Named commands mean this program's
internal commands; see mysql> help . When enabled, the
named commands can be used from any line of the query,
otherwise only from the first line, before an enter.
Disable with --disable-named-commands. This option is
disabled by default.
-i, --ignore-spaces Ignore space after function names.
--init-command=name SQL Command to execute when connecting to MySQL server.
Will automatically be re-executed when reconnecting.
--local-infile Enable/disable LOAD DATA LOCAL INFILE.
-b, --no-beep Turn off beep on error.
-h, --host=name Connect to host.
-H, --html Produce HTML output.
-X, --xml Produce XML output.
--line-numbers Write line numbers for errors.
(Defaults to on; use --skip-line-numbers to disable.)
-L, --skip-line-numbers
Don't write line number for errors.
-n, --unbuffered Flush buffer after each query.
--column-names Write column names in results.
(Defaults to on; use --skip-column-names to disable.)
-N, --skip-column-names
Don't write column names in results.
--sigint-ignore Ignore SIGINT (CTRL-C).
-o, --one-database Ignore statements except those that occur while the
default database is the one named at the command line.
-p, --password[=name]
Password to use when connecting to server. If password is
not given it's asked from the tty.
-W, --pipe Use named pipes to connect to server.
-P, --port=# Port number to use for connection or 0 for default to, in
order of preference, my.cnf, $MYSQL_TCP_PORT,
/etc/services, built-in default (3306).
--prompt=name Set the mysql prompt to this value.
--protocol=name The protocol to use for connection (tcp, socket, pipe,
memory).
-q, --quick Don't cache result, print it row by row. This may slow
down the server if the output is suspended. Doesn't use
history file.
-r, --raw Write fields without conversion. Used with --batch.
--reconnect Reconnect if the connection is lost. Disable with
--disable-reconnect. This option is enabled by default.
(Defaults to on; use --skip-reconnect to disable.)
-s, --silent Be more silent. Print results with a tab as separator,
each row on new line.
--shared-memory-base-name=name
Base name of shared memory.
-S, --socket=name The socket file to use for connection.
--ssl Enable SSL for connection (automatically enabled with
other flags).
--ssl-ca=name CA file in PEM format (check OpenSSL docs, implies
--ssl).
--ssl-capath=name CA directory (check OpenSSL docs, implies --ssl).
--ssl-cert=name X509 cert in PEM format (implies --ssl).
--ssl-cipher=name SSL cipher to use (implies --ssl).
--ssl-key=name X509 key in PEM format (implies --ssl).
--ssl-crl=name Certificate revocation list (implies --ssl).
--ssl-crlpath=name Certificate revocation list path (implies --ssl).
--ssl-verify-server-cert
Verify server's "Common Name" in its cert against
hostname used when connecting. This option is disabled by
default.
-t, --table Output in table format.
--tee=name Append everything into outfile. See interactive help (\h)
also. Does not work in batch mode. Disable with
--disable-tee. This option is disabled by default.
-u, --user=name User for login if not current user.
-U, --safe-updates Only allow UPDATE and DELETE that uses keys.
-U, --i-am-a-dummy Synonym for option --safe-updates, -U.
-v, --verbose Write more. (-v -v -v gives the table output format).
-V, --version Output version information and exit.
-w, --wait Wait and retry if connection is down.
--connect-timeout=# Number of seconds before connection timeout.
--max-allowed-packet=#
The maximum packet length to send to or receive from
server.
--net-buffer-length=#
The buffer size for TCP/IP and socket communication.
--select-limit=# Automatic limit for SELECT when using --safe-updates.
--max-join-size=# Automatic limit for rows in a join when using
--safe-updates.
--secure-auth Refuse client connecting to server if it uses old
(pre-4.1.1) protocol.
(Defaults to on; use --skip-secure-auth to disable.)
--server-arg=name Send embedded server this as a parameter.
--show-warnings Show warnings after every statement.
--plugin-dir=name Directory for client-side plugins.
--default-auth=name Default authentication client-side plugin to use.
--histignore=name A colon-separated list of patterns to keep statements
from getting logged into mysql history.
--binary-mode By default, ASCII '\0' is disallowed and '\r\n' is
translated to '\n'. This switch turns off both features,
and also turns off parsing of all clientcommands except
\C and DELIMITER, in non-interactive mode (for input
piped to mysql or loaded using the 'source' command).
This is necessary when processing output from mysqlbinlog
that may contain blobs.
--connect-expired-password
Notify the server that this client is prepared to handle
expired password sandbox mode.
Default options are read from the following files in the given order:
C:\Windows\my.ini C:\Windows\my.cnf C:\my.ini C:\my.cnf C:\wamp\bin\mysql\mysql5.6.17\my.ini C:\wamp\bin\mysql\mysql5.6.17\my.cnf
The following groups are read: mysql client
The following options may be given as the first argument:
--print-defaults Print the program argument list and exit.
--no-defaults Don't read default options from any option file,
except for login file.
--defaults-file=# Only read default options from the given file #.
--defaults-extra-file=# Read this file after the global files are read.
--defaults-group-suffix=#
Also read groups with concat(group, suffix)
--login-path=# Read this path from the login file.
Variables (--variable-name=value)
and boolean options {FALSE|TRUE} Value (after reading options)
--------------------------------- ----------------------------------------
auto-rehash FALSE
auto-vertical-output FALSE
bind-address (No default value)
character-sets-dir (No default value)
column-type-info FALSE
comments FALSE
compress FALSE
debug-check FALSE
debug-info FALSE
database (No default value)
default-character-set auto
delimiter ;
enable-cleartext-plugin FALSE
vertical FALSE
force FALSE
named-commands FALSE
ignore-spaces FALSE
init-command (No default value)
local-infile FALSE
no-beep FALSE
host (No default value)
html FALSE
xml FALSE
line-numbers TRUE
unbuffered FALSE
column-names TRUE
sigint-ignore FALSE
port 3306
prompt mysql>
quick FALSE
raw FALSE
reconnect FALSE
shared-memory-base-name (No default value)
socket /tmp/mysql.sock
ssl FALSE
ssl-ca (No default value)
ssl-capath (No default value)
ssl-cert (No default value)
ssl-cipher (No default value)
ssl-key (No default value)
ssl-crl (No default value)
ssl-crlpath (No default value)
ssl-verify-server-cert FALSE
table FALSE
user root
safe-updates FALSE
i-am-a-dummy FALSE
connect-timeout 0
max-allowed-packet 16777216
net-buffer-length 16384
select-limit 1000
max-join-size 1000000
secure-auth TRUE
show-warnings FALSE
plugin-dir (No default value)
default-auth (No default value)
histignore (No default value)
binary-mode FALSE
connect-expired-password FALSE
這個mysql輸出似乎沒有明確引用錯誤。 或者是嗎? 有沒有人有想法?
您發布的MySQL輸出是幫助/使用信息,通常在您要求它或錯誤地調用mysql時看到。 您的第一個問題是您嘗試重定向,並使用one-arg Runtime.getRuntime().exec(String)
。
它是windows cmd.exe
或unix / linux shell解釋<
意味着從某個地方重定向stdin
,然后打開並啟動程序,並設置文件描述符來執行該重定向。
Runtime.exec 不是一個命令行處理器,你在executeCommand
使用<
對它沒有意義。 它只是作為另一個參數傳遞給程序mysql
,它不知道如何處理它。
所以,你使用System.out.print((char) byteRead);
只是打印到Java程序的標准輸出,而不是重定向到mysql的標准輸入。 您將不得不使用runtimeProcess.getOutputStream()
,它來自javadoc,“返回連接到子runtimeProcess.getOutputStream()
的正常輸入的輸出流”,然后將文件內容提供給該流,而不是System.out
。
作為最佳實踐,永遠不要使用.exec(String command)
- 再次使用.exec(String[] cmdarray)
,因為.exec 不是命令處理器,只是在空格上打破單個字符串(打破所有使用文件名的嘗試)有空格。
使用String[]
表單可以完全控制實際的args傳遞給您調用的程序。
另請參閱.exec(cmdarry, envp, File dir)
以進一步控制進程。
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.