Apache
/
commons-lang
mirror of https://github.com/apache/commons-lang.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Allow tokenizer state to be adjusted before and after tokenizing 

git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/lang/trunk@424608 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Stephen Colebourne 2006-07-22 17:25:38 +00:00
parent b7b7d7c935
commit 7917cc095b
2 changed files with 74 additions and 41 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

87
src/java/org/apache/commons/lang/text/StrTokenizer.java
View File

@ -16,12 +16,11 @@
package org.apache.commons.lang.text;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.ListIterator;
import java.util.NoSuchElementException;
import org.apache.commons.lang.ArrayUtils;
/**
* Tokenizes a string based based on delimiters (separators)
* and supporting quoting and ignored character concepts.
@ -107,10 +106,8 @@ public class StrTokenizer implements ListIterator, Cloneable {
TSV_TOKENIZER_PROTOTYPE.setIgnoreEmptyTokens(false);
}
/** The text to work on */
/** The text to work on. */
private char chars[];
/** The input text, null if char[] input */
private String text;
/** The parsed tokens */
private String tokens[];
/** The current iteration position */
@ -241,8 +238,7 @@ public class StrTokenizer implements ListIterator, Cloneable {
*/
public StrTokenizer() {
super();
this.text = "";
this.chars = new char[0];
this.chars = null;
}
/**
@ -253,7 +249,6 @@ public class StrTokenizer implements ListIterator, Cloneable {
*/
public StrTokenizer(String input) {
super();
text = input;
if (input != null) {
chars = input.toCharArray();
} else {
@ -331,7 +326,6 @@ public class StrTokenizer implements ListIterator, Cloneable {
*/
public StrTokenizer(char[] input) {
super();
this.text = null;
this.chars = input;
}
@ -417,7 +411,7 @@ public class StrTokenizer implements ListIterator, Cloneable {
* @return the number of matched tokens
*/
public int size() {
tokenize();
checkTokenized();
return tokens.length;
}
@ -451,7 +445,7 @@ public class StrTokenizer implements ListIterator, Cloneable {
* @return the tokens as a String array
*/
public String[] getTokenArray() {
tokenize();
checkTokenized();
return (String[]) tokens.clone();
}
@ -461,7 +455,7 @@ public class StrTokenizer implements ListIterator, Cloneable {
* @return the tokens as a String array
*/
public List getTokenList() {
tokenize();
checkTokenized();
List list = new ArrayList(tokens.length);
for (int i = 0; i < tokens.length; i++) {
list.add(tokens[i]);
@ -492,11 +486,10 @@ public class StrTokenizer implements ListIterator, Cloneable {
*/
public StrTokenizer reset(String input) {
reset();
text = input;
if (input != null) {
chars = input.toCharArray();
this.chars = input.toCharArray();
} else {
chars = null;
this.chars = null;
}
return this;
}
@ -514,8 +507,7 @@ public class StrTokenizer implements ListIterator, Cloneable {
*/
public StrTokenizer reset(char[] input) {
reset();
text = null;
chars = input;
this.chars = input;
return this;
}
@ -527,7 +519,7 @@ public class StrTokenizer implements ListIterator, Cloneable {
* @return true if there are more tokens
*/
public boolean hasNext() {
tokenize();
checkTokenized();
return tokenPos < tokens.length;
}
@ -558,7 +550,7 @@ public class StrTokenizer implements ListIterator, Cloneable {
* @return true if there are previous tokens
*/
public boolean hasPrevious() {
tokenize();
checkTokenized();
return tokenPos > 0;
}
@ -613,42 +605,60 @@ public class StrTokenizer implements ListIterator, Cloneable {
// Implementation
//-----------------------------------------------------------------------
/**
* Performs the tokenization if it hasn't already been done.
* Checks if tokenization has been done, and if not then do it.
*/
private void tokenize() {
private void checkTokenized() {
if (tokens == null) {
tokens = readTokens();
if (chars == null) {
// still call tokenize as subclass may do some work
List split = tokenize(null, 0, 0);
tokens = (String[]) split.toArray(new String[split.size()]);
} else {
List split = tokenize(chars, 0, chars.length);
tokens = (String[]) split.toArray(new String[split.size()]);
}
}
}
/**
* Read all the tokens.
* Internal method to performs the tokenization.
* <p>
* Most users of this class do not need to call this method. This method
* will be called automatically by other (public) methods when required.
* <p>
* This method exists to allow subclasses to add code before or after the
* tokenization. For example, a subclass could alter the character array,
* offset or count to be parsed, or call the tokenizer multiple times on
* multiple strings. It is also be possible to filter the results.
* <p>
* <code>StrTokenizer</code> will always pass a zero offset and a count
* equal to the length of the array to this method, however a subclass
* may pass other values, or even an entirely different array.
*
* @return array containing the tokens.
* @param chars the character array being tokenized, may be null
* @param offset the start position within the character array, must be valid
* @param count the number of characters to tokenize, must be valid
* @return the modifiable list of String tokens, unmodifiable if null array or zero count
*/
private String[] readTokens() {
if (chars == null) {
return ArrayUtils.EMPTY_STRING_ARRAY;
}
int len = chars.length;
if (len == 0) {
return ArrayUtils.EMPTY_STRING_ARRAY;
protected List tokenize(char[] chars, int offset, int count) {
if (chars == null || count == 0) {
return Collections.EMPTY_LIST;
}
StrBuilder buf = new StrBuilder();
List tokens = new ArrayList();
int start = 0;
int pos = offset;
// loop around the entire buffer
while (start >= 0 && start < len) {
while (pos >= 0 && pos < count) {
// find next token
start = readNextToken(chars, start, len, buf, tokens);
pos = readNextToken(chars, pos, count, buf, tokens);
// handle case where end of string is a delimiter
if (start >= len) {
if (pos >= count) {
addToken(tokens, "");
}
}
return (String[]) tokens.toArray(new String[tokens.size()]);
return tokens;
}
/**
@ -1058,10 +1068,7 @@ public class StrTokenizer implements ListIterator, Cloneable {
* @return the string content being parsed
*/
public String getContent() {
if (text == null) {
text = new String(chars);
}
return text;
return new String(chars);
}
//-----------------------------------------------------------------------

28
src/test/org/apache/commons/lang/text/StrTokenizerTest.java
View File

@ -17,6 +17,7 @@
package org.apache.commons.lang.text;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.NoSuchElementException;
@ -531,7 +532,7 @@ public class StrTokenizerTest extends TestCase {
public void testGetContent() {
String input = "a b c \"d e\" f ";
StrTokenizer tok = new StrTokenizer(input);
assertSame(input, tok.getContent());
assertEquals(input, tok.getContent());
tok = new StrTokenizer(input.toCharArray());
assertEquals(input, tok.getContent());
@ -804,4 +805,29 @@ public class StrTokenizerTest extends TestCase {
assertEquals(false, tkn.hasNext());
}
//-----------------------------------------------------------------------
public void testTokenizeSubclassInputChange() {
StrTokenizer tkn = new StrTokenizer("a b c d e") {
protected List tokenize(char[] chars, int offset, int count) {
return super.tokenize("w x y z".toCharArray(), 2, 5);
}
};
assertEquals("x", tkn.next());
assertEquals("y", tkn.next());
}
//-----------------------------------------------------------------------
public void testTokenizeSubclassOutputChange() {
StrTokenizer tkn = new StrTokenizer("a b c") {
protected List tokenize(char[] chars, int offset, int count) {
List list = super.tokenize(chars, offset, count);
Collections.reverse(list);
return list;
}
};
assertEquals("c", tkn.next());
assertEquals("b", tkn.next());
assertEquals("a", tkn.next());
}
}