[String] Improve StringFactory
- Add get(char)
- Let all impl make use of cached interned strings for ASCII chars
- Add unit tests
Change-Id: I1786fa927cfdc6feb65382b81b25e973de4d9a43
diff --git a/jcommons/org.eclipse.statet.jcommons.util-tests/src/org/eclipse/statet/jcommons/string/BasicStringFactoryTest.java b/jcommons/org.eclipse.statet.jcommons.util-tests/src/org/eclipse/statet/jcommons/string/BasicStringFactoryTest.java
new file mode 100644
index 0000000..c044773
--- /dev/null
+++ b/jcommons/org.eclipse.statet.jcommons.util-tests/src/org/eclipse/statet/jcommons/string/BasicStringFactoryTest.java
@@ -0,0 +1,116 @@
+/*=============================================================================#
+ # Copyright (c) 2021 Stephan Wahlbrink and others.
+ #
+ # This program and the accompanying materials are made available under the
+ # terms of the Eclipse Public License 2.0 which is available at
+ # https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
+ # which is available at https://www.apache.org/licenses/LICENSE-2.0.
+ #
+ # SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
+ #
+ # Contributors:
+ # Stephan Wahlbrink <sw@wahlbrink.eu> - initial API and implementation
+ #=============================================================================*/
+
+package org.eclipse.statet.jcommons.string;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import static org.eclipse.statet.jcommons.lang.ObjectUtils.nonNullLateInit;
+
+import org.junit.jupiter.api.Test;
+
+import org.eclipse.statet.jcommons.lang.NonNullByDefault;
+
+
+@NonNullByDefault
+public class BasicStringFactoryTest {
+
+
+ protected StringFactory factory= nonNullLateInit();
+
+
+ public BasicStringFactoryTest() {
+ }
+
+
+ protected StringFactory create() {
+ return BasicStringFactory.INSTANCE;
+ }
+
+
+ @Test
+ public void get_CharSequence() {
+ this.factory= create();
+ final String s= this.factory.get(new StringBuilder("ab"));
+ assertEquals("ab", s);
+ }
+
+ @Test
+ public void get_CharSequence_emtpy() {
+ this.factory= create();
+ final String s= this.factory.get(new StringBuilder(""));
+ assertTrue("" == s);
+ }
+
+ @Test
+ public void get_CharSequence_asciiChar() {
+ this.factory= create();
+ final String s= this.factory.get(new StringBuilder("a"));
+ assertTrue("a" == s);
+ }
+
+
+ @Test
+ public void get_CharArrayString() {
+ this.factory= create();
+ final String s= this.factory.get(new CharArrayString("ab"));
+ assertEquals("ab", s);
+ }
+
+ @Test
+ public void get_CharArrayString_emtpy() {
+ this.factory= create();
+ final String s= this.factory.get(new CharArrayString(""));
+ assertTrue("" == s);
+ }
+
+ @Test
+ public void get_CharArrayString_asciiChar() {
+ this.factory= create();
+ final String s= this.factory.get(new CharArrayString("a"));
+ assertTrue("a" == s);
+ }
+
+
+ @Test
+ public void get_String() {
+ this.factory= create();
+ final String s= this.factory.get(new String("ab"));
+ assertEquals("ab", s);
+ }
+
+ @Test
+ public void get_String_emtpy() {
+ this.factory= create();
+ final String s= this.factory.get(new String(""));
+ assertTrue("" == s);
+ }
+
+ @Test
+ public void get_String_asciiChar() {
+ this.factory= create();
+ final String s= this.factory.get(new String("a"));
+ assertTrue("a" == s);
+ }
+
+
+ @Test
+ public void get_Char_asciiChar() {
+ this.factory= create();
+ final String s= this.factory.get('a');
+ assertTrue("a" == s);
+ }
+
+}
diff --git a/jcommons/org.eclipse.statet.jcommons.util-tests/src/org/eclipse/statet/jcommons/string/CachedStringFactoryTest.java b/jcommons/org.eclipse.statet.jcommons.util-tests/src/org/eclipse/statet/jcommons/string/CachedStringFactoryTest.java
new file mode 100644
index 0000000..40214d1
--- /dev/null
+++ b/jcommons/org.eclipse.statet.jcommons.util-tests/src/org/eclipse/statet/jcommons/string/CachedStringFactoryTest.java
@@ -0,0 +1,59 @@
+/*=============================================================================#
+ # Copyright (c) 2021 Stephan Wahlbrink and others.
+ #
+ # This program and the accompanying materials are made available under the
+ # terms of the Eclipse Public License 2.0 which is available at
+ # https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
+ # which is available at https://www.apache.org/licenses/LICENSE-2.0.
+ #
+ # SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
+ #
+ # Contributors:
+ # Stephan Wahlbrink <sw@wahlbrink.eu> - initial API and implementation
+ #=============================================================================*/
+
+package org.eclipse.statet.jcommons.string;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.junit.jupiter.api.Test;
+
+import org.eclipse.statet.jcommons.lang.NonNullByDefault;
+
+
+@NonNullByDefault
+public class CachedStringFactoryTest extends BasicStringFactoryTest {
+
+
+ @Override
+ protected StringFactory create() {
+ return new CacheStringFactory(10);
+ }
+
+
+ @Test
+ public void get_CharSequence_cached() {
+ this.factory= create();
+ final String s= this.factory.get(new StringBuilder("ab"));
+ assertEquals("ab", s);
+ assertTrue(s == this.factory.get(new StringBuilder("ab")));
+ }
+
+ @Test
+ public void get_CharArrayString_cached() {
+ this.factory= create();
+ final String s= this.factory.get(new CharArrayString("ab"));
+ assertEquals("ab", s);
+ assertTrue(s == this.factory.get(new CharArrayString("ab")));
+ }
+
+ @Test
+ public void get_String_cached() {
+ this.factory= create();
+ final String s= this.factory.get(new String("ab"));
+ assertEquals("ab", s);
+ assertTrue(s == this.factory.get(new String("ab")));
+ }
+
+}
diff --git a/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/BasicStringFactory.java b/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/BasicStringFactory.java
index e09285c..6ab2bea 100644
--- a/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/BasicStringFactory.java
+++ b/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/BasicStringFactory.java
@@ -14,6 +14,7 @@
package org.eclipse.statet.jcommons.string;
+import org.eclipse.statet.jcommons.lang.NonNull;
import org.eclipse.statet.jcommons.lang.NonNullByDefault;
@@ -24,22 +25,68 @@
public static final BasicStringFactory INSTANCE= new BasicStringFactory();
+ static final int CHARTABLE_SIZE= 0x7F;
+ static final @NonNull String[] CHARTABLE;
+ static {
+ CHARTABLE= new @NonNull String[CHARTABLE_SIZE];
+ for (char i= 0; i < CHARTABLE_SIZE; i++) {
+ CHARTABLE[i]= String.valueOf(i).intern();
+ }
+ }
+
+
public BasicStringFactory() {
}
@Override
public String get(final CharSequence s) {
- return s.toString();
+ switch (s.length()) {
+ case 0:
+ return ""; //$NON-NLS-1$
+ case 1:
+ return get(s.charAt(0));
+ default:
+ return s.toString();
+ }
}
@Override
public String get(final CharArrayString s) {
- return s.toString();
+ switch (s.length()) {
+ case 0:
+ return ""; //$NON-NLS-1$
+ case 1:
+ return get(s.charAt(0));
+ default:
+ return s.toString();
+ }
}
@Override
public String get(final String s) {
+ switch (s.length()) {
+ case 0:
+ return ""; //$NON-NLS-1$
+ case 1:
+ return get(s.charAt(0), s);
+ default:
+ return s;
+ }
+ }
+
+ @Override
+ public String get(final char c) {
+ if (c >= 0 && c < CHARTABLE_SIZE) {
+ return CHARTABLE[c];
+ }
+ return String.valueOf(c);
+ }
+
+ private String get(final char c, final String s) {
+ if (c >= 0 && c < CHARTABLE_SIZE) {
+ return CHARTABLE[c];
+ }
return s;
}
diff --git a/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/CacheStringFactory.java b/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/CacheStringFactory.java
index 4138ca3..247c069 100644
--- a/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/CacheStringFactory.java
+++ b/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/CacheStringFactory.java
@@ -14,25 +14,22 @@
package org.eclipse.statet.jcommons.string;
+import static org.eclipse.statet.jcommons.string.BasicStringFactory.CHARTABLE;
+import static org.eclipse.statet.jcommons.string.BasicStringFactory.CHARTABLE_SIZE;
+
+import org.eclipse.statet.jcommons.lang.NonNullByDefault;
+
/**
* A cache of fixed size, interning string
*/
+@NonNullByDefault
public class CacheStringFactory implements StringFactory {
private static final int HASHSET_SIZE= 0x400;
private static final int HASHSET_MASK= HASHSET_SIZE - 1; // bits true from right
- private static final int CHARTABLE_SIZE= 0x7F;
- private static final String[] CHARTABLE;
- static {
- CHARTABLE= new String[CHARTABLE_SIZE];
- for (char i= 0; i < CHARTABLE_SIZE; i++) {
- CHARTABLE[i]= String.valueOf(i).intern();
- }
- }
-
private final String[] values;
@@ -46,12 +43,12 @@
@Override
- public String get(final CharArrayString s) {
+ public String get(final CharSequence s) {
switch (s.length()) {
case 0:
return ""; //$NON-NLS-1$
case 1:
- return getChar(s.charAt(0));
+ return get(s.charAt(0));
default:
if (s.length() > this.maxCachedLength) {
return s.toString();
@@ -61,12 +58,12 @@
}
@Override
- public String get(final CharSequence s) {
+ public String get(final CharArrayString s) {
switch (s.length()) {
case 0:
return ""; //$NON-NLS-1$
case 1:
- return getChar(s.charAt(0));
+ return get(s.charAt(0));
default:
if (s.length() > this.maxCachedLength) {
return s.toString();
@@ -81,7 +78,7 @@
case 0:
return ""; //$NON-NLS-1$
case 1:
- return getChar(s.charAt(0), s);
+ return get(s.charAt(0), s);
default:
if (s.length() > this.maxCachedLength) {
return s;
@@ -91,7 +88,8 @@
}
- private String getChar(final char c) {
+ @Override
+ public String get(final char c) {
if (c >= 0 && c < CHARTABLE_SIZE) {
// this.statCharmap++;
return CHARTABLE[c];
@@ -108,7 +106,7 @@
}
}
- private String getChar(final char c, final String s) {
+ private String get(final char c, final String s) {
if (c >= 0 && c < CHARTABLE_SIZE) {
// this.statCharmap++;
return CHARTABLE[c];
@@ -125,6 +123,7 @@
}
}
+
private int computeHash(final CharSequence s) {
int hashCode= 0;
int length= s.length();
diff --git a/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/StringFactory.java b/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/StringFactory.java
index 4c72615..ed15322 100644
--- a/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/StringFactory.java
+++ b/jcommons/org.eclipse.statet.jcommons.util/src/org/eclipse/statet/jcommons/string/StringFactory.java
@@ -24,10 +24,10 @@
public interface StringFactory {
- String get(CharArrayString s);
-
String get(CharSequence s);
-
+ String get(CharArrayString s);
String get(String s);
+ String get(char c);
+
}
