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/*NOTE: TestKeyRange is AccessExample changed to test Db.key_range.
* See comments with ADDED for specific areas of change.
*/
/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1997-2002
* Sleepycat Software. All rights reserved.
*
* $Id: TestKeyRange.java,v 1.4 2002/08/16 19:35:55 dda Exp $
*/
package com.sleepycat.test;
import com.sleepycat.db.*;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.StringReader;
import java.io.Reader;
import java.io.IOException;
import java.io.PrintStream;
public class TestKeyRange
{
private static final String FileName = "access.db";
public TestKeyRange()
{
}
private static void usage()
{
System.err.println("usage: TestKeyRange\n");
System.exit(1);
}
public static void main(String argv[])
{
try
{
TestKeyRange app = new TestKeyRange();
app.run();
}
catch (DbException dbe)
{
System.err.println("TestKeyRange: " + dbe.toString());
System.exit(1);
}
catch (FileNotFoundException fnfe)
{
System.err.println("TestKeyRange: " + fnfe.toString());
System.exit(1);
}
System.exit(0);
}
// Prompts for a line, and keeps prompting until a non blank
// line is returned. Returns null on error.
//
static public String askForLine(Reader reader,
PrintStream out, String prompt)
{
String result = "";
while (result != null && result.length() == 0) {
out.print(prompt);
out.flush();
result = getLine(reader);
}
return result;
}
// Not terribly efficient, but does the job.
// Works for reading a line from stdin or a file.
// Returns null on EOF. If EOF appears in the middle
// of a line, returns that line, then null on next call.
//
static public String getLine(Reader reader)
{
StringBuffer b = new StringBuffer();
int c;
try {
while ((c = reader.read()) != -1 && c != '\n') {
if (c != '\r')
b.append((char)c);
}
}
catch (IOException ioe) {
c = -1;
}
if (c == -1 && b.length() == 0)
return null;
else
return b.toString();
}
public void run()
throws DbException, FileNotFoundException
{
// Remove the previous database.
new File(FileName).delete();
// Create the database object.
// There is no environment for this simple example.
Db table = new Db(null, 0);
table.set_error_stream(System.err);
table.set_errpfx("TestKeyRange");
table.open(null, FileName, null, Db.DB_BTREE, Db.DB_CREATE, 0644);
//
// Insert records into the database, where the key is the user
// input and the data is the user input in reverse order.
//
Reader reader = new StringReader("abc\nmiddle\nzend\nmoremiddle\nZED\nMAMAMIA");
int count= 0;/*ADDED*/
for (;;) {
String line = askForLine(reader, System.out, "input>");
if (line == null)
break;
String reversed = (new StringBuffer(line)).reverse().toString();
// See definition of StringDbt below
//
StringDbt key = new StringDbt(line);
StringDbt data = new StringDbt(reversed);
try
{
int err;
if ((err = table.put(null, key, data, 0)) == Db.DB_KEYEXIST) {
System.out.println("Key " + line + " already exists.");
}
}
catch (DbException dbe)
{
System.out.println(dbe.toString());
}
System.out.println("");
/*START ADDED*/
{
if (count++ > 0) {
DbKeyRange range = new DbKeyRange();
table.key_range(null, key, range, 0);
System.out.println("less: " + range.less);
System.out.println("equal: " + range.equal);
System.out.println("greater: " + range.greater);
}
}
/*END ADDED*/
}
// Acquire an iterator for the table.
Dbc iterator;
iterator = table.cursor(null, 0);
// Walk through the table, printing the key/data pairs.
// See class StringDbt defined below.
//
StringDbt key = new StringDbt();
StringDbt data = new StringDbt();
while (iterator.get(key, data, Db.DB_NEXT) == 0)
{
System.out.println(key.getString() + " : " + data.getString());
}
iterator.close();
table.close(0);
}
// Here's an example of how you can extend a Dbt in a straightforward
// way to allow easy storage/retrieval of strings, or whatever
// kind of data you wish. We've declared it as a static inner
// class, but it need not be.
//
static /*inner*/
class StringDbt extends Dbt
{
StringDbt()
{
set_flags(Db.DB_DBT_MALLOC); // tell Db to allocate on retrieval
}
StringDbt(String value)
{
setString(value);
set_flags(Db.DB_DBT_MALLOC); // tell Db to allocate on retrieval
}
void setString(String value)
{
set_data(value.getBytes());
set_size(value.length());
}
String getString()
{
return new String(get_data(), 0, get_size());
}
}
}
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