| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.hadoop.sqoop.util; |
| |
| import java.io.IOException; |
| import java.io.OutputStream; |
| import java.nio.ByteBuffer; |
| import java.nio.CharBuffer; |
| import java.sql.ResultSet; |
| import java.sql.ResultSetMetaData; |
| import java.sql.SQLException; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| |
| /** |
| * Utility methods to format and print ResultSet objects |
| * |
| * |
| */ |
| public class ResultSetPrinter { |
| |
| public static final Log LOG = LogFactory.getLog(ResultSetPrinter.class.getName()); |
| |
| // max output width to allocate to any column of the printed results. |
| private static final int MAX_COL_WIDTH = 20; |
| |
| // length of the byte buffer, in bytes, to allocate. |
| private static final int BUFFER_LEN = 4096; |
| |
| // maximum number of characters to deserialize from the stringbuilder |
| // into the byte buffer at a time. Factor of 2 off b/c of Unicode. |
| private static final int MAX_CHARS = 2048; |
| |
| private ByteBuffer bytebuf; |
| private char [] charArray; |
| |
| public ResultSetPrinter() { |
| bytebuf = ByteBuffer.allocate(BUFFER_LEN); |
| charArray = new char[MAX_CHARS]; |
| } |
| |
| /** |
| * Print 'str' to the string builder, padded to 'width' chars |
| */ |
| private static void printPadded(StringBuilder sb, String str, int width) { |
| int numPad; |
| if (null == str) { |
| sb.append("(null)"); |
| numPad = width - "(null)".length(); |
| } else { |
| sb.append(str); |
| numPad = width - str.length(); |
| } |
| |
| for (int i = 0; i < numPad; i++) { |
| sb.append(' '); |
| } |
| } |
| |
| |
| /** |
| * Takes the contents of the StringBuilder and prints it on the OutputStream |
| */ |
| private void sendToStream(StringBuilder sb, OutputStream os) throws IOException { |
| |
| int pos = 0; // current pos in the string builder |
| int len = sb.length(); // total length (in characters) to send to os. |
| CharBuffer charbuf = bytebuf.asCharBuffer(); |
| |
| while (pos < len) { |
| int copyLen = Math.min(sb.length(), MAX_CHARS); |
| sb.getChars(pos, copyLen, charArray, 0); |
| |
| charbuf.put(charArray, 0, copyLen); |
| os.write(bytebuf.array()); |
| |
| pos += copyLen; |
| } |
| |
| } |
| |
| private static final String COL_SEPARATOR = " | "; |
| |
| /** |
| * Format the contents of the ResultSet into something that could be printed |
| * neatly; the results are appended to the supplied StringBuilder. |
| */ |
| public final void printResultSet(OutputStream os, ResultSet results) throws IOException { |
| try { |
| StringBuilder sbNames = new StringBuilder(); |
| int cols = results.getMetaData().getColumnCount(); |
| |
| int [] colWidths = new int[cols]; |
| ResultSetMetaData metadata = results.getMetaData(); |
| for (int i = 1; i < cols + 1; i++) { |
| String colName = metadata.getColumnName(i); |
| colWidths[i - 1] = Math.min(metadata.getColumnDisplaySize(i), MAX_COL_WIDTH); |
| if (colName == null || colName.equals("")) { |
| colName = metadata.getColumnLabel(i) + "*"; |
| } |
| printPadded(sbNames, colName, colWidths[i - 1]); |
| sbNames.append(COL_SEPARATOR); |
| } |
| sbNames.append('\n'); |
| |
| StringBuilder sbPad = new StringBuilder(); |
| for (int i = 0; i < cols; i++) { |
| for (int j = 0; j < COL_SEPARATOR.length() + colWidths[i]; j++) { |
| sbPad.append('-'); |
| } |
| } |
| sbPad.append('\n'); |
| |
| sendToStream(sbPad, os); |
| sendToStream(sbNames, os); |
| sendToStream(sbPad, os); |
| |
| while (results.next()) { |
| StringBuilder sb = new StringBuilder(); |
| for (int i = 1; i < cols + 1; i++) { |
| printPadded(sb, results.getString(i), colWidths[i - 1]); |
| sb.append(COL_SEPARATOR); |
| } |
| sb.append('\n'); |
| sendToStream(sb, os); |
| } |
| |
| sendToStream(sbPad, os); |
| } catch (SQLException sqlException) { |
| LOG.error("Error reading from database: " + sqlException.toString()); |
| } |
| } |
| |
| } |
| |