从java.sql.PreparedStatement获取查询

193
在我的代码中,我使用了java.sql.PreparedStatement
然后我执行setString()方法来填充预处理语句的通配符。
在调用executeQuery()方法并执行查询之前,有没有一种方式可以检索(并打印出)最终查询?我只是为了调试目的而这样做。
8个回答

193

在JDBC API合同中没有明确定义,但如果你幸运的话,相关的JDBC驱动程序可能会通过调用PreparedStatement#toString()返回完整的SQL。也就是说:

System.out.println(preparedStatement);
根据我的经验,目前至少支持此功能的是 PostgreSQL 8.x 和 MySQL 5.x JDBC 驱动程序。
如果你的 JDBC 驱动程序不支持此功能,最好的方法是使用语句包装器来记录所有调用 setXxx() 方法的信息,并最终在 toString() 上基于记录的信息填充 SQL 字符串。一个现有的库,可以实现这个功能,就是P6Spy。同时,向 JDBC 驱动程序的开发团队提出增强请求并希望他们也会实现所需的 toString() 行为。

32
你可以尝试在设置绑定值之后,在准备好的语句上调用toString()
PreparedStatement statement = connection.prepareStatement(aSQLStatement);
System.out.println("Before : " + statement.toString());
query.setString(1, "Hello");
query.setString(2, "World");
System.out.println("After : " + statement.toString());

这在使用JDBC MySQL驱动程序时有效,但我不确定在其他情况下是否有效。您可能需要跟踪所有绑定并将其打印出来。

以上代码的示例输出。

Before : com.mysql.jdbc.JDBC4PreparedStatement@fa9cf: SELECT * FROM test WHERE blah1=** NOT SPECIFIED ** and blah2=** NOT SPECIFIED **
After : com.mysql.jdbc.JDBC4PreparedStatement@fa9cf: SELECT * FROM test WHERE blah1='Hello' and blah2='World'

52
抱歉,不支持使用Oracle :( - Dchucks
10
不要使用Sqlite! - Earth Engine
4
您可以通过以下方式从Oracle驱动程序中获取原始的SQL语句:((OraclePreparedStatementWrapper) preparedStatement).getOriginalSql() - divideByZero
4
不支持Postgres或DB2。 - user1205577
5
11g中的OraclePreparedStatementWrapper不是公共的,无法从包外部访问,因此该代码现在会失败@divideByZero。 - mcvkr
显示剩余3条评论

26

对于那些正在寻找Oracle解决方案的人,我从Log4Jdbc的代码中制作了一种方法。您需要提供查询和传递给preparedStatement的参数,因为从中检索它们有点麻烦:

private String generateActualSql(String sqlQuery, Object... parameters) {
    String[] parts = sqlQuery.split("\\?");
    StringBuilder sb = new StringBuilder();

    // This might be wrong if some '?' are used as litteral '?'
    for (int i = 0; i < parts.length; i++) {
        String part = parts[i];
        sb.append(part);
        if (i < parameters.length) {
            sb.append(formatParameter(parameters[i]));
        }
    }

    return sb.toString();
}

private String formatParameter(Object parameter) {
    if (parameter == null) {
        return "NULL";
    } else {
        if (parameter instanceof String) {
            return "'" + ((String) parameter).replace("'", "''") + "'";
        } else if (parameter instanceof Timestamp) {
            return "to_timestamp('" + new SimpleDateFormat("MM/dd/yyyy HH:mm:ss.SSS").
                    format(parameter) + "', 'mm/dd/yyyy hh24:mi:ss.ff3')";
        } else if (parameter instanceof Date) {
            return "to_date('" + new SimpleDateFormat("MM/dd/yyyy HH:mm:ss").
                    format(parameter) + "', 'mm/dd/yyyy hh24:mi:ss')";
        } else if (parameter instanceof Boolean) {
            return ((Boolean) parameter).booleanValue() ? "1" : "0";
        } else {
            return parameter.toString();
        }
    }
}

3
OP想要从PreparedStatement对象中获取生成的查询。 - expert
@ruslan 1. 不,OP没有指定。2. 对于Oracle来说是不可能的。 - qwertzguy
10
在调用executeQuery()方法并执行查询之前,有没有一种方法可以检索(并打印出)最终的查询语句?他明确表示想要传递参数给PreparedStatement后得到最终的查询语句。 - expert
作为一个Oracle数据库用户,我会给它点赞。它看起来比其他方法更简单。 - RAHUL ROY
如何传递 Object... parameters 的值? - Suresh

12

2
这是一个非常好的教程,介绍如何使用log4j:http://www.cubrid.org/store_java_logs_to_databdase_using_log4j。 - esengineer

8

如果你只想记录查询,那么在jdbc url中添加 'logger' 和 'profileSQL':

&logger=com.mysql.jdbc.log.Slf4JLogger&profileSQL=true

那么你将得到以下的SQL语句:
2016-01-14 10:09:43  INFO MySQL - FETCH created: Thu Jan 14 10:09:43 CST 2016 duration: 1 connection: 19130945 statement: 999 resultset: 0
2016-01-14 10:09:43  INFO MySQL - QUERY created: Thu Jan 14 10:09:43 CST 2016 duration: 1 connection: 19130945 statement: 999 resultset: 0 message: SET sql_mode='NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES'
2016-01-14 10:09:43  INFO MySQL - FETCH created: Thu Jan 14 10:09:43 CST 2016 duration: 1 connection: 19130945 statement: 999 resultset: 0
2016-01-14 10:09:43  INFO MySQL - QUERY created: Thu Jan 14 10:09:43 CST 2016 duration: 2 connection: 19130945 statement: 13 resultset: 17 message: select 1
2016-01-14 10:09:43  INFO MySQL - FETCH created: Thu Jan 14 10:09:43 CST 2016 duration: 0 connection: 19130945 statement: 13 resultset: 17
2016-01-14 10:09:43  INFO MySQL - QUERY created: Thu Jan 14 10:09:43 CST 2016 duration: 1 connection: 19130945 statement: 15 resultset: 18 message: select @@session.tx_read_only
2016-01-14 10:09:43  INFO MySQL - FETCH created: Thu Jan 14 10:09:43 CST 2016 duration: 0 connection: 19130945 statement: 15 resultset: 18
2016-01-14 10:09:43  INFO MySQL - QUERY created: Thu Jan 14 10:09:43 CST 2016 duration: 2 connection: 19130945 statement: 14 resultset: 0 message: update sequence set seq=seq+incr where name='demo' and seq=4602
2016-01-14 10:09:43  INFO MySQL - FETCH created: Thu Jan 14 10:09:43 CST 2016 duration: 0 connection: 19130945 statement: 14 resultset: 0

默认日志记录器是:

com.mysql.jdbc.log.StandardLogger

MySQL JDBC 属性列表:https://dev.mysql.com/doc/connector-j/zh/connector-j-reference-configuration-properties.html


我们能否获得一个完整的示例? - john k

4
我制定了一种解决方法来解决这个问题。 要获取更多细节,请访问下面的链接 http://code-outofbox.blogspot.com/2015/07/java-prepared-statement-print-values.html 解决方案:
// Initialize connection
PreparedStatement prepStmt = connection.prepareStatement(sql);

PreparedStatementHelper prepHelper = new PreparedStatementHelper(prepStmt);

// User prepHelper.setXXX(indx++, value);
// .....

try {
   Pattern pattern = Pattern.compile("\\?");
   Matcher matcher = pattern.matcher(sql);
   StringBuffer sb = new StringBuffer();
   int indx = 1;  // Parameter begin with index 1
   while (matcher.find()) {
 matcher.appendReplacement(sb, prepHelper.getParameter(indx++));
   }
   matcher.appendTail(sb);
   LOGGER.debug("Executing Query [" + sb.toString() + "] with Database[" + /*db name*/ + "] ...");
   } catch (Exception ex) {
    LOGGER.debug("Executing Query [" + sql + "] with Database[" +  /*db name*/+ "] ...");
}

/****************************************************/

package java.sql;

import java.io.InputStream;
import java.io.Reader;
import java.math.BigDecimal;
import java.net.URL;
import java.sql.Array;
import java.sql.Blob;
import java.sql.Clob;
import java.sql.Connection;
import java.sql.Date;
import java.sql.NClob;
import java.sql.ParameterMetaData;
import java.sql.PreparedStatement;
import java.sql.Ref;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.RowId;
import java.sql.SQLException;
import java.sql.SQLWarning;
import java.sql.SQLXML;
import java.sql.Time;
import java.sql.Timestamp;
import java.util.Calendar;

public class PreparedStatementHelper implements PreparedStatement {

 private PreparedStatement prepStmt;
 private String[] values;

 public PreparedStatementHelper(PreparedStatement prepStmt) throws SQLException {
  this.prepStmt = prepStmt;
  this.values = new String[this.prepStmt.getParameterMetaData().getParameterCount()];
 }

 public String getParameter(int index) {
  String value = this.values[index-1];
  return String.valueOf(value);
 }

 private void setParameter(int index, Object value) {
  String valueStr = "";
  if (value instanceof String) {
   valueStr = "'" + String.valueOf(value).replaceAll("'", "''") + "'";
  } else if (value instanceof Integer) {
   valueStr = String.valueOf(value);
  } else if (value instanceof Date || value instanceof Time || value instanceof Timestamp) {
   valueStr = "'" + String.valueOf(value) + "'";
  } else {
   valueStr = String.valueOf(value);
  }
  this.values[index-1] = valueStr;
 }

 @Override
 public ResultSet executeQuery(String sql) throws SQLException {
  return this.prepStmt.executeQuery(sql);
 }

 @Override
 public int executeUpdate(String sql) throws SQLException {
  return this.prepStmt.executeUpdate(sql);
 }

 @Override
 public void close() throws SQLException {
  this.prepStmt.close();

 }

 @Override
 public int getMaxFieldSize() throws SQLException {
  return this.prepStmt.getMaxFieldSize();
 }

 @Override
 public void setMaxFieldSize(int max) throws SQLException {
  this.prepStmt.setMaxFieldSize(max);
 }

 @Override
 public int getMaxRows() throws SQLException {
  return this.prepStmt.getMaxRows();
 }

 @Override
 public void setMaxRows(int max) throws SQLException {
  this.prepStmt.setMaxRows(max);
 }

 @Override
 public void setEscapeProcessing(boolean enable) throws SQLException {
  this.prepStmt.setEscapeProcessing(enable);
 }

 @Override
 public int getQueryTimeout() throws SQLException {
  return this.prepStmt.getQueryTimeout();
 }

 @Override
 public void setQueryTimeout(int seconds) throws SQLException {
  this.prepStmt.setQueryTimeout(seconds);
 }

 @Override
 public void cancel() throws SQLException {
  this.prepStmt.cancel();
 }

 @Override
 public SQLWarning getWarnings() throws SQLException {
  return this.prepStmt.getWarnings();
 }

 @Override
 public void clearWarnings() throws SQLException {
  this.prepStmt.clearWarnings();
 }

 @Override
 public void setCursorName(String name) throws SQLException {
  this.prepStmt.setCursorName(name);
 }

 @Override
 public boolean execute(String sql) throws SQLException {
  return this.prepStmt.execute(sql);
 }

 @Override
 public ResultSet getResultSet() throws SQLException {
  return this.prepStmt.getResultSet();
 }

 @Override
 public int getUpdateCount() throws SQLException {
  return this.prepStmt.getUpdateCount();
 }

 @Override
 public boolean getMoreResults() throws SQLException {
  return this.prepStmt.getMoreResults();
 }

 @Override
 public void setFetchDirection(int direction) throws SQLException {
  this.prepStmt.setFetchDirection(direction);
 }

 @Override
 public int getFetchDirection() throws SQLException {
  return this.prepStmt.getFetchDirection();
 }

 @Override
 public void setFetchSize(int rows) throws SQLException {
  this.prepStmt.setFetchSize(rows);
 }

 @Override
 public int getFetchSize() throws SQLException {
  return this.prepStmt.getFetchSize();
 }

 @Override
 public int getResultSetConcurrency() throws SQLException {
  return this.prepStmt.getResultSetConcurrency();
 }

 @Override
 public int getResultSetType() throws SQLException {
  return this.prepStmt.getResultSetType();
 }

 @Override
 public void addBatch(String sql) throws SQLException {
  this.prepStmt.addBatch(sql);
 }

 @Override
 public void clearBatch() throws SQLException {
  this.prepStmt.clearBatch();
 }

 @Override
 public int[] executeBatch() throws SQLException {
  return this.prepStmt.executeBatch();
 }

 @Override
 public Connection getConnection() throws SQLException {
  return this.prepStmt.getConnection();
 }

 @Override
 public boolean getMoreResults(int current) throws SQLException {
  return this.prepStmt.getMoreResults(current);
 }

 @Override
 public ResultSet getGeneratedKeys() throws SQLException {
  return this.prepStmt.getGeneratedKeys();
 }

 @Override
 public int executeUpdate(String sql, int autoGeneratedKeys) throws SQLException {
  return this.prepStmt.executeUpdate(sql, autoGeneratedKeys);
 }

 @Override
 public int executeUpdate(String sql, int[] columnIndexes) throws SQLException {
  return this.prepStmt.executeUpdate(sql, columnIndexes);
 }

 @Override
 public int executeUpdate(String sql, String[] columnNames) throws SQLException {
  return this.prepStmt.executeUpdate(sql, columnNames);
 }

 @Override
 public boolean execute(String sql, int autoGeneratedKeys) throws SQLException {
  return this.prepStmt.execute(sql, autoGeneratedKeys);
 }

 @Override
 public boolean execute(String sql, int[] columnIndexes) throws SQLException {
  return this.prepStmt.execute(sql, columnIndexes);
 }

 @Override
 public boolean execute(String sql, String[] columnNames) throws SQLException {
  return this.prepStmt.execute(sql, columnNames);
 }

 @Override
 public int getResultSetHoldability() throws SQLException {
  return this.prepStmt.getResultSetHoldability();
 }

 @Override
 public boolean isClosed() throws SQLException {
  return this.prepStmt.isClosed();
 }

 @Override
 public void setPoolable(boolean poolable) throws SQLException {
  this.prepStmt.setPoolable(poolable);
 }

 @Override
 public boolean isPoolable() throws SQLException {
  return this.prepStmt.isPoolable();
 }

 @Override
 public <T> T unwrap(Class<T> iface) throws SQLException {
  return this.prepStmt.unwrap(iface);
 }

 @Override
 public boolean isWrapperFor(Class<?> iface) throws SQLException {
  return this.prepStmt.isWrapperFor(iface);
 }

 @Override
 public ResultSet executeQuery() throws SQLException {
  return this.prepStmt.executeQuery();
 }

 @Override
 public int executeUpdate() throws SQLException {
  return this.prepStmt.executeUpdate();
 }

 @Override
 public void setNull(int parameterIndex, int sqlType) throws SQLException {
  this.prepStmt.setNull(parameterIndex, sqlType);
  setParameter(parameterIndex, null);
 }

 @Override
 public void setBoolean(int parameterIndex, boolean x) throws SQLException {
  this.prepStmt.setBoolean(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setByte(int parameterIndex, byte x) throws SQLException {
  this.prepStmt.setByte(parameterIndex, x);
  // TODO Add to tree set
 }

 @Override
 public void setShort(int parameterIndex, short x) throws SQLException {
  this.prepStmt.setShort(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setInt(int parameterIndex, int x) throws SQLException {
  this.prepStmt.setInt(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setLong(int parameterIndex, long x) throws SQLException {
  this.prepStmt.setLong(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setFloat(int parameterIndex, float x) throws SQLException {
  this.prepStmt.setFloat(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setDouble(int parameterIndex, double x) throws SQLException {
  this.prepStmt.setDouble(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setBigDecimal(int parameterIndex, BigDecimal x) throws SQLException {
  this.prepStmt.setBigDecimal(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setString(int parameterIndex, String x) throws SQLException {
  this.prepStmt.setString(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setBytes(int parameterIndex, byte[] x) throws SQLException {
  this.prepStmt.setBytes(parameterIndex, x);
  // TODO Add to tree set
 }

 @Override
 public void setDate(int parameterIndex, Date x) throws SQLException {
  this.prepStmt.setDate(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setTime(int parameterIndex, Time x) throws SQLException {
  this.prepStmt.setTime(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setTimestamp(int parameterIndex, Timestamp x) throws SQLException {
  this.prepStmt.setTimestamp(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setAsciiStream(int parameterIndex, InputStream x, int length) throws SQLException {
  this.prepStmt.setAsciiStream(parameterIndex, x, length);
 }

 @SuppressWarnings("deprecation")
 @Override
 public void setUnicodeStream(int parameterIndex, InputStream x, int length) throws SQLException {
  this.prepStmt.setUnicodeStream(parameterIndex, x, length);
 }

 @Override
 public void setBinaryStream(int parameterIndex, InputStream x, int length) throws SQLException {
  this.prepStmt.setBinaryStream(parameterIndex, x, length);
 }

 @Override
 public void clearParameters() throws SQLException {
  this.prepStmt.clearParameters();
 }

 @Override
 public void setObject(int parameterIndex, Object x, int targetSqlType) throws SQLException {
  this.prepStmt.setObject(parameterIndex, x, targetSqlType);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setObject(int parameterIndex, Object x) throws SQLException {
  this.prepStmt.setObject(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public boolean execute() throws SQLException {
  return this.prepStmt.execute();
 }

 @Override
 public void addBatch() throws SQLException {
  this.prepStmt.addBatch();
 }

 @Override
 public void setCharacterStream(int parameterIndex, Reader reader, int length) throws SQLException {
  this.prepStmt.setCharacterStream(parameterIndex, reader, length);
 }

 @Override
 public void setRef(int parameterIndex, Ref x) throws SQLException {
  this.prepStmt.setRef(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setBlob(int parameterIndex, Blob x) throws SQLException {
  this.prepStmt.setBlob(parameterIndex, x);
 }

 @Override
 public void setClob(int parameterIndex, Clob x) throws SQLException {
  this.prepStmt.setClob(parameterIndex, x);
 }

 @Override
 public void setArray(int parameterIndex, Array x) throws SQLException {
  this.prepStmt.setArray(parameterIndex, x);
  // TODO Add to tree set
 }

 @Override
 public ResultSetMetaData getMetaData() throws SQLException {
  return this.prepStmt.getMetaData();
 }

 @Override
 public void setDate(int parameterIndex, Date x, Calendar cal) throws SQLException {
  this.prepStmt.setDate(parameterIndex, x, cal);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setTime(int parameterIndex, Time x, Calendar cal) throws SQLException {
  this.prepStmt.setTime(parameterIndex, x, cal);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setTimestamp(int parameterIndex, Timestamp x, Calendar cal) throws SQLException {
  this.prepStmt.setTimestamp(parameterIndex, x, cal);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setNull(int parameterIndex, int sqlType, String typeName) throws SQLException {
  this.prepStmt.setNull(parameterIndex, sqlType, typeName);
  setParameter(parameterIndex, null);
 }

 @Override
 public void setURL(int parameterIndex, URL x) throws SQLException {
  this.prepStmt.setURL(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public ParameterMetaData getParameterMetaData() throws SQLException {
  return this.prepStmt.getParameterMetaData();
 }

 @Override
 public void setRowId(int parameterIndex, RowId x) throws SQLException {
  this.prepStmt.setRowId(parameterIndex, x);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setNString(int parameterIndex, String value) throws SQLException {
  this.prepStmt.setNString(parameterIndex, value);
  setParameter(parameterIndex, value);
 }

 @Override
 public void setNCharacterStream(int parameterIndex, Reader value, long length) throws SQLException {
  this.prepStmt.setNCharacterStream(parameterIndex, value, length);
 }

 @Override
 public void setNClob(int parameterIndex, NClob value) throws SQLException {
  this.prepStmt.setNClob(parameterIndex, value);
 }

 @Override
 public void setClob(int parameterIndex, Reader reader, long length) throws SQLException {
  this.prepStmt.setClob(parameterIndex, reader, length);
 }

 @Override
 public void setBlob(int parameterIndex, InputStream inputStream, long length) throws SQLException {
  this.prepStmt.setBlob(parameterIndex, inputStream, length);
 }

 @Override
 public void setNClob(int parameterIndex, Reader reader, long length) throws SQLException {
  this.prepStmt.setNClob(parameterIndex, reader, length);
 }

 @Override
 public void setSQLXML(int parameterIndex, SQLXML xmlObject) throws SQLException {
  this.prepStmt.setSQLXML(parameterIndex, xmlObject);
  setParameter(parameterIndex, xmlObject);
 }

 @Override
 public void setObject(int parameterIndex, Object x, int targetSqlType, int scaleOrLength) throws SQLException {
  this.prepStmt.setObject(parameterIndex, x, targetSqlType, scaleOrLength);
  setParameter(parameterIndex, x);
 }

 @Override
 public void setAsciiStream(int parameterIndex, InputStream x, long length) throws SQLException {
  this.prepStmt.setAsciiStream(parameterIndex, x, length);
 }

 @Override
 public void setBinaryStream(int parameterIndex, InputStream x, long length) throws SQLException {
  this.prepStmt.setBinaryStream(parameterIndex, x, length);
 }

 @Override
 public void setCharacterStream(int parameterIndex, Reader reader, long length) throws SQLException {
  this.prepStmt.setCharacterStream(parameterIndex, reader, length);
 }

 @Override
 public void setAsciiStream(int parameterIndex, InputStream x) throws SQLException {
  this.prepStmt.setAsciiStream(parameterIndex, x);
  // TODO Add to tree set
 }

 @Override
 public void setBinaryStream(int parameterIndex, InputStream x) throws SQLException {
  this.prepStmt.setBinaryStream(parameterIndex, x);
 }

 @Override
 public void setCharacterStream(int parameterIndex, Reader reader) throws SQLException {
  this.prepStmt.setCharacterStream(parameterIndex, reader);
 }

 @Override
 public void setNCharacterStream(int parameterIndex, Reader value) throws SQLException {
  this.prepStmt.setNCharacterStream(parameterIndex, value);
 }

 @Override
 public void setClob(int parameterIndex, Reader reader) throws SQLException {
  this.prepStmt.setClob(parameterIndex, reader);
  // TODO Add to tree set
 }

 @Override
 public void setBlob(int parameterIndex, InputStream inputStream) throws SQLException {
  this.prepStmt.setBlob(parameterIndex, inputStream);
 }

 @Override
 public void setNClob(int parameterIndex, Reader reader) throws SQLException {
  this.prepStmt.setNClob(parameterIndex, reader);
 }

}

在阅读您的答案之前,我已经实现了几乎完全相同的解决方法。但我希望我使用的是mysql,这样我就可以查看源代码并扩展他们所拥有的任何PreparedStatement实现,而不必覆盖200个PreparedStatement方法。 - Brent Sandstrom

3
有点小技巧,但对我来说可以很好地工作:
Integer id = 2;
String query = "SELECT * FROM table WHERE id = ?";
PreparedStatement statement = m_connection.prepareStatement( query );
statement.setObject( 1, value );
String statementText = statement.toString();
query = statementText.substring( statementText.indexOf( ": " ) + 2 );

1
我认为可以在数据库和应用程序之间放置代理,然后观察通信。我不熟悉用于此操作的软件。

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