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comparison src/main/java/org/monetdb/util/Exporter.java @ 391:f523727db392

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Moved Java classes from packages starting with nl.cwi.monetdb.* to package org.monetdb.* This naming complies to the Java Package Naming convention as MonetDB's main website is www.monetdb.org.
author Martin van Dinther <martin.van.dinther@monetdbsolutions.com>
date Thu, 12 Nov 2020 22:02:01 +0100 (2020-11-12)
parents src/main/java/nl/cwi/monetdb/util/Exporter.java@54137aeb1f92
children bf9f6b6ecf40
comparison
equal deleted inserted replaced
390:6199e0be3c6e 391:f523727db392
1 /*
2 * This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
5 *
6 * Copyright 1997 - July 2008 CWI, August 2008 - 2020 MonetDB B.V.
7 */
8
9 package org.monetdb.util;
10
11 import java.io.PrintWriter;
12 import java.sql.ResultSet;
13 import java.sql.SQLException;
14
15 public abstract class Exporter {
16 protected PrintWriter out;
17 protected boolean useSchema;
18
19 protected Exporter(final PrintWriter out) {
20 this.out = out;
21 }
22
23 public abstract void dumpSchema(
24 final java.sql.DatabaseMetaData dbmd,
25 final String type,
26 final String schema,
27 final String name) throws SQLException;
28
29 public abstract void dumpResultSet(final ResultSet rs) throws SQLException;
30
31 public abstract void setProperty(final int type, final int value) throws Exception;
32 public abstract int getProperty(final int type) throws Exception;
33
34
35 //=== shared utilities
36
37 public final void useSchemas(final boolean use) {
38 useSchema = use;
39 }
40
41 /**
42 * returns the given string between two double quotes for usage as
43 * identifier such as column or table or schema name in SQL queries.
44 *
45 * @param in the string to quote
46 * @return the quoted string
47 */
48 protected static final String dq(final String in) {
49 return "\"" + in.replaceAll("\\\\", "\\\\\\\\").replaceAll("\"", "\\\\\"") + "\"";
50 }
51
52 /**
53 * returns the given string between two single quotes for usage as
54 * string literal in SQL queries.
55 *
56 * @param in the string to quote
57 * @return the quoted string
58 */
59 protected static final String q(final String in) {
60 return "'" + in.replaceAll("\\\\", "\\\\\\\\").replaceAll("'", "\\\\'") + "'";
61 }
62
63 /**
64 * Simple helper function to repeat a given character a number of times.
65 *
66 * @param chr the character to repeat
67 * @param cnt the number of times to repeat chr
68 * @return a String holding cnt times chr
69 */
70 protected static final String repeat(final char chr, final int cnt) {
71 final char[] buf = new char[cnt];
72 java.util.Arrays.fill(buf, chr);
73 return new String(buf);
74 }
75
76 /**
77 * Utility method to fetch the "query" value from sys.tables for a specific view or table in a specific schema
78 * The "query" value contains the original SQL view creation text or the ON clause text when it is a REMOTE TABLE
79 *
80 * @param con the JDBC connection, may not be null
81 * @param schema the schem name, may not be null or empty
82 * @param name the view or table name, may not be null or empty
83 * @return the value of the "query" field for the specified view/table name and schema. It can return null.
84 */
85 protected static final String fetchSysTablesQueryValue(
86 final java.sql.Connection con,
87 final String schema,
88 final String name)
89 {
90 java.sql.Statement stmt = null;
91 ResultSet rs = null;
92 String val = null;
93 try {
94 stmt = con.createStatement();
95 final String cmd = "SELECT query FROM sys.tables WHERE name = '" + name
96 + "' and schema_id IN (SELECT id FROM sys.schemas WHERE name = '" + schema + "')";
97 rs = stmt.executeQuery(cmd);
98 if (rs != null) {
99 if (rs.next()) {
100 val = rs.getString(1);
101 }
102 }
103 } catch (SQLException se) {
104 /* ignore */
105 } finally {
106 // free resources
107 if (rs != null) {
108 try { rs.close(); } catch (SQLException se) { /* ignore */ }
109 }
110 if (stmt != null) {
111 try { stmt.close(); } catch (SQLException se) { /* ignore */ }
112 }
113 }
114 return val;
115 }
116 }