/**
* 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.drill.common.util;
import io.netty.buffer.ByteBuf;
import org.apache.commons.lang3.StringEscapeUtils;
import org.apache.commons.lang3.StringUtils;
public class DrillStringUtils {
/**
* Converts the long number into more human readable string.
*/
public static String readable(long bytes) {
int unit = 1024;
long absBytes = Math.abs(bytes);
if (absBytes < unit) {
return bytes + " B";
}
int exp = (int) (Math.log(absBytes) / Math.log(unit));
char pre = ("KMGTPE").charAt(exp-1);
return String.format("%s%.1f %ciB", (bytes == absBytes ? "" : "-"), absBytes / Math.pow(unit, exp), pre);
}
/**
* Unescapes any Java literals found in the {@code String}.
* For example, it will turn a sequence of {@code '\'} and
* {@code 'n'} into a newline character, unless the {@code '\'}
* is preceded by another {@code '\'}.
*
* @param input the {@code String} to unescape, may be null
* @return a new unescaped {@code String}, {@code null} if null string input
*/
public static final String unescapeJava(String input) {
return StringEscapeUtils.unescapeJava(input);
}
/**
* Escapes the characters in a {@code String} according to Java string literal
* rules.
*
* Deals correctly with quotes and control-chars (tab, backslash, cr, ff,
* etc.) so, for example, a tab becomes the characters {@code '\\'} and
* {@code 't'}.
*
* Example:
* <pre>
* input string: He didn't say, "Stop!"
* output string: He didn't say, \"Stop!\"
* </pre>
*
* @param input String to escape values in, may be null
* @return String with escaped values, {@code null} if null string input
*/
public static final String escapeJava(String input) {
return StringEscapeUtils.escapeJava(input);
}
public static final String escapeNewLines(String input) {
if (input == null) {
return null;
}
StringBuilder result = new StringBuilder();
boolean sawNewline = false;
for (int i = 0; i < input.length(); i++) {
char curChar = input.charAt(i);
if (curChar == '\r' || curChar == '\n') {
if (sawNewline) {
continue;
}
sawNewline = true;
result.append("\\n");
} else {
sawNewline = false;
result.append(curChar);
}
}
return result.toString();
}
/**
* Copied form commons-lang 2.x code as common-lang 3.x has this API removed.
* (http://commons.apache.org/proper/commons-lang/article3_0.html#StringEscapeUtils.escapeSql)
* @param str
* @return
*/
public static String escapeSql(String str) {
return (str == null) ? null : StringUtils.replace(str, "'", "''");
}
/**
* Return a printable representation of a byte buffer, escaping the non-printable
* bytes as '\\xNN' where NN is the hexadecimal representation of such bytes.
*
* This function does not modify the {@code readerIndex} and {@code writerIndex}
* of the byte buffer.
*/
public static String toBinaryString(ByteBuf buf, int strStart, int strEnd) {
StringBuilder result = new StringBuilder();
for (int i = strStart; i < strEnd ; ++i) {
appendByte(result, buf.getByte(i));
}
return result.toString();
}
/**
* Return a printable representation of a byte array, escaping the non-printable
* bytes as '\\xNN' where NN is the hexadecimal representation of such bytes.
*/
public static String toBinaryString(byte[] buf) {
return toBinaryString(buf, 0, buf.length);
}
/**
* Return a printable representation of a byte array, escaping the non-printable
* bytes as '\\xNN' where NN is the hexadecimal representation of such bytes.
*/
public static String toBinaryString(byte[] buf, int strStart, int strEnd) {
StringBuilder result = new StringBuilder();
for (int i = strStart; i < strEnd; ++i) {
appendByte(result, buf[i]);
}
return result.toString();
}
private static void appendByte(StringBuilder result, byte b) {
int ch = b & 0xFF;
if ( (ch >= '0' && ch <= '9')
|| (ch >= 'A' && ch <= 'Z')
|| (ch >= 'a' && ch <= 'z')
|| " `~!@#$%^&*()-_=+[]{}|;:'\",.<>/?".indexOf(ch) >= 0 ) {
result.append((char)ch);
} else {
result.append(String.format("\\x%02X", ch));
}
}
/**
* parsing a hex encoded binary string and write to an output buffer.
*
* This function does not modify the {@code readerIndex} and {@code writerIndex}
* of the byte buffer.
*
* @return Index in the byte buffer just after the last written byte.
*/
public static int parseBinaryString(ByteBuf str, int strStart, int strEnd, ByteBuf out) {
int dstEnd = 0;
for (int i = strStart; i < strEnd; i++) {
byte b = str.getByte(i);
if (b == '\\'
&& strEnd > i+3
&& (str.getByte(i+1) == 'x' || str.getByte(i+1) == 'X')) {
// ok, take next 2 hex digits.
byte hd1 = str.getByte(i+2);
byte hd2 = str.getByte(i+3);
if (isHexDigit(hd1) && isHexDigit(hd2)) { // [a-fA-F0-9]
// turn hex ASCII digit -> number
b = (byte) ((toBinaryFromHex(hd1) << 4) + toBinaryFromHex(hd2));
i += 3; // skip 3
}
}
out.setByte(dstEnd++, b);
}
return dstEnd;
}
/**
* Takes a ASCII digit in the range A-F0-9 and returns
* the corresponding integer/ordinal value.
* @param ch The hex digit.
* @return The converted hex value as a byte.
*/
private static byte toBinaryFromHex(byte ch) {
if ( ch >= 'A' && ch <= 'F' ) {
return (byte) ((byte)10 + (byte) (ch - 'A'));
} else if ( ch >= 'a' && ch <= 'f' ) {
return (byte) ((byte)10 + (byte) (ch - 'a'));
}
return (byte) (ch - '0');
}
private static boolean isHexDigit(byte c) {
return (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F') || (c >= '0' && c <= '9');
}
}