The Boolean class has cache for true and false and using it, will save
memory and will faster than using create new instance of boolean.
Using JMH[1] with a code test[2] the result was:
Benchmark Mode Samples
Mean Mean error Units
m.BooleanBenchmark.newInstanceBoolean thrpt 20 49801.326
369.897 ops/s
m.BooleanBenchmark.newInstanceString thrpt 20
365.080 27.537 ops/s
m.BooleanBenchmark.valueOfBoolean thrpt 20 764906233.316
9623009.653 ops/s
m.BooleanBenchmark.valueOfString thrpt 20
371.174 28.216 ops/s
The diff is on attachment or can is downloading the webdrev here:
https://dl.dropboxusercontent.com/u/16109193/open_jdk/boolean_instance_of.zip
[1] http://openjdk.java.net/projects/code-tools/jmh/
[2]
@State(Scope.Thread)
@OutputTimeUnit(TimeUnit.SECONDS)
public class BooleanBenchmark {
private static final int SIZE = 1_000_000;
private List<String> booleanString;
private boolean[] booleans;
{
booleans = new boolean[SIZE];
booleanString = new ArrayList<>(SIZE);
for (int index = 0; index < SIZE; index++) {
if (index % 2 == 0) {
booleans[index] = true;
booleanString.add(Boolean.TRUE.toString());
} else {
booleans[index] = false;
booleanString.add(Boolean.FALSE.toString());
}
}
}
@GenerateMicroBenchmark
public void valueOfBoolean() {
for(boolean b: booleans) {
Boolean result = b;
}
}
@GenerateMicroBenchmark
public void valueOfString() {
for(String b: booleanString) {
Boolean result = Boolean.valueOf(b);
}
}
@GenerateMicroBenchmark
public void newInstanceBoolean() {
for(boolean b: booleans) {
Boolean result = new Boolean(b);
}
}
@GenerateMicroBenchmark
public void newInstanceString() {
for(String b: booleanString) {
Boolean result = new Boolean(b);
}
}
}
--
Atenciosamente.
Otávio Gonçalves de Santana
blog: http://otaviosantana.blogspot.com.br/
twitter: http://twitter.com/otaviojava
site: http://www.otaviojava.com.br
(11) 98255-3513
diff -r 28d1de89ff27 src/share/classes/java/net/Socket.java
--- a/src/share/classes/java/net/Socket.java Thu May 22 12:54:02 2014 -0700
+++ b/src/share/classes/java/net/Socket.java Sat May 24 10:55:43 2014 -0300
@@ -1017,7 +1017,7 @@
if (isClosed())
throw new SocketException("Socket is closed");
if (!on) {
- getImpl().setOption(SocketOptions.SO_LINGER, new Boolean(on));
+ getImpl().setOption(SocketOptions.SO_LINGER, on);
} else {
if (linger < 0) {
throw new IllegalArgumentException("invalid value for
SO_LINGER");
diff -r 28d1de89ff27 src/share/classes/sun/font/SunFontManager.java
--- a/src/share/classes/sun/font/SunFontManager.java Thu May 22 12:54:02
2014 -0700
+++ b/src/share/classes/sun/font/SunFontManager.java Sat May 24 10:55:43
2014 -0300
@@ -2871,8 +2871,7 @@
new java.security.PrivilegedAction<Object>() {
public Object run() {
SecurityManager sm = System.getSecurityManager();
- return new Boolean
- (sm instanceof sun.applet.AppletSecurity);
+ return sm instanceof sun.applet.AppletSecurity;
}
});
return appletSM.booleanValue();
diff -r 28d1de89ff27
src/share/classes/sun/management/StackTraceElementCompositeData.java
--- a/src/share/classes/sun/management/StackTraceElementCompositeData.java
Thu May 22 12:54:02 2014 -0700
+++ b/src/share/classes/sun/management/StackTraceElementCompositeData.java
Sat May 24 10:55:43 2014 -0300
@@ -68,7 +68,7 @@
ste.getMethodName(),
ste.getFileName(),
new Integer(ste.getLineNumber()),
- new Boolean(ste.isNativeMethod()),
+ ste.isNativeMethod(),
};
try {
return new CompositeDataSupport(stackTraceElementCompositeType,
diff -r 28d1de89ff27
src/share/classes/sun/management/ThreadInfoCompositeData.java
--- a/src/share/classes/sun/management/ThreadInfoCompositeData.java Thu May
22 12:54:02 2014 -0700
+++ b/src/share/classes/sun/management/ThreadInfoCompositeData.java Sat May
24 10:55:43 2014 -0300
@@ -120,8 +120,8 @@
new Long(threadInfo.getLockOwnerId()),
threadInfo.getLockOwnerName(),
stackTraceData,
- new Boolean(threadInfo.isSuspended()),
- new Boolean(threadInfo.isInNative()),
+ threadInfo.isSuspended(),
+ threadInfo.isInNative(),
lockedMonitorsData,
lockedSyncsData,
};
diff -r 28d1de89ff27 src/share/classes/sun/management/VMOptionCompositeData.java
--- a/src/share/classes/sun/management/VMOptionCompositeData.java Thu May
22 12:54:02 2014 -0700
+++ b/src/share/classes/sun/management/VMOptionCompositeData.java Sat May
24 10:55:43 2014 -0300
@@ -59,7 +59,7 @@
final Object[] vmOptionItemValues = {
option.getName(),
option.getValue(),
- new Boolean(option.isWriteable()),
+ option.isWriteable(),
option.getOrigin().toString(),
};
diff -r 28d1de89ff27
src/share/classes/sun/reflect/UnsafeBooleanFieldAccessorImpl.java
--- a/src/share/classes/sun/reflect/UnsafeBooleanFieldAccessorImpl.java Thu May
22 12:54:02 2014 -0700
+++ b/src/share/classes/sun/reflect/UnsafeBooleanFieldAccessorImpl.java Sat May
24 10:55:43 2014 -0300
@@ -33,7 +33,7 @@
}
public Object get(Object obj) throws IllegalArgumentException {
- return new Boolean(getBoolean(obj));
+ return getBoolean(obj);
}
public boolean getBoolean(Object obj) throws IllegalArgumentException {
diff -r 28d1de89ff27
src/share/classes/sun/reflect/UnsafeQualifiedBooleanFieldAccessorImpl.java
---
a/src/share/classes/sun/reflect/UnsafeQualifiedBooleanFieldAccessorImpl.java
Thu May 22 12:54:02 2014 -0700
+++
b/src/share/classes/sun/reflect/UnsafeQualifiedBooleanFieldAccessorImpl.java
Sat May 24 10:55:43 2014 -0300
@@ -35,7 +35,7 @@
}
public Object get(Object obj) throws IllegalArgumentException {
- return new Boolean(getBoolean(obj));
+ return getBoolean(obj);
}
public boolean getBoolean(Object obj) throws IllegalArgumentException {
diff -r 28d1de89ff27
src/share/classes/sun/reflect/UnsafeQualifiedStaticBooleanFieldAccessorImpl.java
---
a/src/share/classes/sun/reflect/UnsafeQualifiedStaticBooleanFieldAccessorImpl.java
Thu May 22 12:54:02 2014 -0700
+++
b/src/share/classes/sun/reflect/UnsafeQualifiedStaticBooleanFieldAccessorImpl.java
Sat May 24 10:55:43 2014 -0300
@@ -35,7 +35,7 @@
}
public Object get(Object obj) throws IllegalArgumentException {
- return new Boolean(getBoolean(obj));
+ return getBoolean(obj);
}
public boolean getBoolean(Object obj) throws IllegalArgumentException {
diff -r 28d1de89ff27
src/share/classes/sun/reflect/UnsafeStaticBooleanFieldAccessorImpl.java
--- a/src/share/classes/sun/reflect/UnsafeStaticBooleanFieldAccessorImpl.java
Thu May 22 12:54:02 2014 -0700
+++ b/src/share/classes/sun/reflect/UnsafeStaticBooleanFieldAccessorImpl.java
Sat May 24 10:55:43 2014 -0300
@@ -33,7 +33,7 @@
}
public Object get(Object obj) throws IllegalArgumentException {
- return new Boolean(getBoolean(obj));
+ return getBoolean(obj);
}
public boolean getBoolean(Object obj) throws IllegalArgumentException {
diff -r 28d1de89ff27 src/share/classes/sun/security/jgss/GSSManagerImpl.java
--- a/src/share/classes/sun/security/jgss/GSSManagerImpl.java Thu May 22
12:54:02 2014 -0700
+++ b/src/share/classes/sun/security/jgss/GSSManagerImpl.java Sat May 24
10:55:43 2014 -0300
@@ -50,8 +50,8 @@
if (osname.startsWith("SunOS") ||
osname.contains("OS X") ||
osname.startsWith("Linux")) {
- return new Boolean(System.getProperty
- (USE_NATIVE_PROP));
+ return Boolean.valueOf(System.getProperty
+ (USE_NATIVE_PROP));
}
return Boolean.FALSE;
}
diff -r 28d1de89ff27 src/share/classes/sun/security/provider/PolicyFile.java
--- a/src/share/classes/sun/security/provider/PolicyFile.java Thu May 22
12:54:02 2014 -0700
+++ b/src/share/classes/sun/security/provider/PolicyFile.java Sat May 24
10:55:43 2014 -0300
@@ -1271,7 +1271,7 @@
Boolean imp = AccessController.doPrivileged
(new PrivilegedAction<Boolean>() {
public Boolean run() {
- return new Boolean(entry.getCodeSource().implies(cs));
+ return entry.getCodeSource().implies(cs);
}
});
if (!imp.booleanValue()) {
