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Posted to commits@groovy.apache.org by pa...@apache.org on 2023/01/26 07:18:27 UTC
[groovy] branch GROOVY_4_0_X updated (3a80f2c31c -> 4b7ac86ce3)
This is an automated email from the ASF dual-hosted git repository.
paulk pushed a change to branch GROOVY_4_0_X
in repository https://gitbox.apache.org/repos/asf/groovy.git
from 3a80f2c31c GROOVY-10881: FastStringUtils does not work in an OSGi environment
new d17f500097 Minor improvements to 'Differences with Java' documentation page
new 4b7ac86ce3 Minor improvements to 'Differences with Java' documentation page (additional minor tweaks)
The 2 revisions listed above as "new" are entirely new to this
repository and will be described in separate emails. The revisions
listed as "add" were already present in the repository and have only
been added to this reference.
Summary of changes:
src/spec/doc/assets/css/style.css | 4 +-
src/spec/doc/core-differences-java.adoc | 139 ++++++++++++++-------------
src/spec/test/DifferencesFromJavaTest.groovy | 18 ++--
3 files changed, 84 insertions(+), 77 deletions(-)
[groovy] 01/02: Minor improvements to 'Differences with Java' documentation page
Posted by pa...@apache.org.
This is an automated email from the ASF dual-hosted git repository.
paulk pushed a commit to branch GROOVY_4_0_X
in repository https://gitbox.apache.org/repos/asf/groovy.git
commit d17f5000978910102e772ef3a3f3258da1b61f62
Author: Alex Golub <a1...@gmail.com>
AuthorDate: Wed Jan 25 20:13:32 2023 +0200
Minor improvements to 'Differences with Java' documentation page
---
src/spec/doc/core-differences-java.adoc | 98 +++++++++++++++-------------
src/spec/test/DifferencesFromJavaTest.groovy | 18 ++---
2 files changed, 61 insertions(+), 55 deletions(-)
diff --git a/src/spec/doc/core-differences-java.adoc b/src/spec/doc/core-differences-java.adoc
index 55b17b6bb2..9a4bce77ab 100644
--- a/src/spec/doc/core-differences-java.adoc
+++ b/src/spec/doc/core-differences-java.adoc
@@ -126,7 +126,7 @@ include::../test/DifferencesFromJavaTest.groovy[tags=packageprivate_field,indent
== ARM blocks
-Java 7 introduced ARM (Automatic Resource Management) blocks like this:
+Java 7 introduced ARM (Automatic Resource Management) blocks (also know as try-with-resources) blocks like this:
[source,java]
----
@@ -298,18 +298,22 @@ Luckily, Java auto boxes and unboxes primitives when they are passed as paramete
// a few shell blocks use "ruby" code style as it is more forgiving than Java or Groovy
// it's not straight code after all, but might as well be a little pretty
-[source,ruby]
+[source,java]
----
-jshell> class Main {
- ...> float f1 = 1.0f;
- ...> Float f2 = 2.0f;
- ...> float add(Float a1, float a2) { return a1 + a2; }
- ...> Float calc() { return add(f1, f2); } // <1>
- ...> }
-| created class Main
+public class Main {
+
+ float f1 = 1.0f;
+ Float f2 = 2.0f;
-jshell> new Main().calc()
-$2 ==> 3.0
+ float add(Float a1, float a2) { return a1 + a2; }
+
+ Float calc() { return add(f1, f2); } // <1>
+
+ public static void main(String[] args) {
+ Float calcResult = new Main().calc();
+ System.out.println(calcResult); // => 3.0
+ }
+}
----
<1> The `add` method expects wrapper then primitive type arguments,
but we are supplying parameters with a primitive then wrapper type.
@@ -317,53 +321,51 @@ Similarly, the return type from `add` is primitive, but we need the wrapper type
Groovy does the same:
-[source,ruby]
+[source,groovy]
----
-groovy:000> class Main {
-groovy:001> float f1 = 1.0f
-groovy:002> Float f2 = 2.0f
-groovy:003> float add(Float a1, float a2) { a1 + a2 }
-groovy:004> Float calc() { add(f1, f2) }
-groovy:005> }
-===> true
-groovy:000> new Main().calc()
-===> 3.0
+class Main {
+
+ float f1 = 1.0f
+ Float f2 = 2.0f
+
+ float add(Float a1, float a2) { a1 + a2 }
+
+ Float calc() { add(f1, f2) }
+}
+
+assert new Main().calc() == 3.0
----
Groovy, also supports primitives and object types, however, it goes a little further
in pushing OO purity; it tries hard to treat _everything_ as an object.
-Any primitive typed variable or field can be treated like an object and it
-will be link:core-object-orientation.html#_primitive_types[autowrapped] as needed.
+Any primitive typed variable or field can be treated like an object, and it
+will be link:core-object-orientation.html#_primitive_types[auto-wrapped] as needed.
While primitive types might be used under the covers,
-their use should be indistinguishable from normal object use whenever possible
+their use should be indistinguishable from normal object use whenever possible,
and they will be boxed/unboxed as needed.
Here is a little example using Java trying to (incorrectly for Java) dereference a primitive `float`:
-[source,ruby]
+[source,java]
----
-jshell> class Main {
- ...> public float z1 = 0.0f;
- ...> }
-| created class Main
+class Main {
+
+ public float z1 = 0.0f;
-jshell> new Main().z1.equals(1.0f)
-| Error:
-| float cannot be dereferenced
-| new Main().z1.equals(1.0f)
-| ^------------------^
+ public static void main(String[] args){
+ new Main().z1.equals(1.0f); // DOES NOT COMPILE, Cannot resolve method 'equals(float)'
+ }
+}
----
The same example using Groovy compiles and runs successfully:
-[source,ruby]
+[source,groovy]
----
-groovy:000> class Main {
-groovy:001> float z1 = 0.0f
-groovy:002> }
-===> true
-groovy:000> new Main().z1.equals(1.0f)
-===> false
+class Main {
+ float z1 = 0.0f
+}
+assert !(new Main().z1.equals(1.0f))
----
Because of Groovy's additional use of un/boxing, it does not follow
@@ -463,8 +465,10 @@ https://docs.oracle.com/javase/specs/jls/se7/html/jls-5.html[conversions].
| float | N | C | C | C | C | C | - | Y
| double | N | C | C | C | C | C | C | -
|============================================================================================
-^*^ 'Y' indicates a conversion Java can make, 'C' indicates a conversion Java can make when there is an explicit cast,
-'T` indicates a conversion Java can make but data is truncated, 'N' indicates a conversion Java can't make.
+* 'Y' indicates a conversion Java can make +
+* 'C' indicates a conversion Java can make when there is an explicit cast +
+* 'T` indicates a conversion Java can make but data is truncated +
+* 'N' indicates a conversion Java can't make
Groovy expands greatly on this.
@@ -492,9 +496,11 @@ Groovy expands greatly on this.
| Double | T | T | D | T | D | T | T | D | D | T | D | T | D | D | T | B | - | Y
| BigDecimal | T | T | D | D | D | D | D | D | D | D | D | D | D | T | D | T | D | -
|=================================================================================================================================================================================================================
-^*^ 'Y' indicates a conversion Groovy can make, 'D' indicates a conversion Groovy can make when compiled dynamically or
-explicitly cast, 'T' indicates a conversion Groovy can make but data is truncated, 'B' indicates a boxing/unboxing
-operation, 'N' indicates a conversion Groovy can't make.
+* 'Y' indicates a conversion Groovy can make +
+* 'D' indicates a conversion Groovy can make when compiled dynamically or explicitly cast +
+* 'T' indicates a conversion Groovy can make but data is truncated +
+* 'B' indicates a boxing/unboxing operation +
+* 'N' indicates a conversion Groovy can't make.
The truncation uses <<{core-semantics}#the-groovy-truth,Groovy Truth>> when converting to `boolean`/`Boolean`. Converting
from a number to a character casts the `Number.intvalue()` to `char`. Groovy constructs `BigInteger` and `BigDecimal`
diff --git a/src/spec/test/DifferencesFromJavaTest.groovy b/src/spec/test/DifferencesFromJavaTest.groovy
index 0b9d83f178..5e12d2bcf6 100644
--- a/src/spec/test/DifferencesFromJavaTest.groovy
+++ b/src/spec/test/DifferencesFromJavaTest.groovy
@@ -162,25 +162,25 @@ assert (x.'this$0').is(y)
import org.codehaus.groovy.runtime.typehandling.GroovyCastException;
// tag::type_depends_on_quoting_AND_whether_we_actually_interpolate[]
-assert 'c'.getClass()==String
-assert "c".getClass()==String
-assert "c${1}".getClass() in GString
+assert 'c'.class == String
+assert "c".class == String
+assert "c${1}".class in GString
// end::type_depends_on_quoting_AND_whether_we_actually_interpolate[]
// tag::single_char_strings_are_autocasted[]
-char a='a'
-assert Character.digit(a, 16)==10 : 'But Groovy does boxing'
-assert Character.digit((char) 'a', 16)==10
+char a = 'a'
+assert Character.digit(a, 16) == 10: 'But Groovy does boxing'
+assert Character.digit((char) 'a', 16) == 10
try {
- assert Character.digit('a', 16)==10
+ assert Character.digit('a', 16) == 10
assert false: 'Need explicit cast'
} catch(MissingMethodException e) {
}
// end::single_char_strings_are_autocasted[]
// tag::chars_c_vs_groovy_cast[]
// for single char strings, both are the same
-assert ((char) "c").class==Character
-assert ("c" as char).class==Character
+assert ((char) "c").class == Character
+assert ("c" as char).class == Character
// for multi char strings they are not
try {
[groovy] 02/02: Minor improvements to 'Differences with Java' documentation page (additional minor tweaks)
Posted by pa...@apache.org.
This is an automated email from the ASF dual-hosted git repository.
paulk pushed a commit to branch GROOVY_4_0_X
in repository https://gitbox.apache.org/repos/asf/groovy.git
commit 4b7ac86ce3b99440ad982852f42fad42162b3c42
Author: Paul King <pa...@asert.com.au>
AuthorDate: Thu Jan 26 15:59:31 2023 +1000
Minor improvements to 'Differences with Java' documentation page (additional minor tweaks)
---
src/spec/doc/assets/css/style.css | 4 ++-
src/spec/doc/core-differences-java.adoc | 47 ++++++++++++++++-----------------
2 files changed, 26 insertions(+), 25 deletions(-)
diff --git a/src/spec/doc/assets/css/style.css b/src/spec/doc/assets/css/style.css
index 3562670d2e..3f752ad44d 100644
--- a/src/spec/doc/assets/css/style.css
+++ b/src/spec/doc/assets/css/style.css
@@ -420,6 +420,8 @@ code {
color: #db4800;
}
+code.rotate { width: 20px; height: 100px; white-space: nowrap; transform: rotate(-90deg); background: transparent; border: 0px; display: inline-block; position:relative; left: 40px; bottom: -50px; }
+
ul, ol, dl {
font-size: 1em;
line-height: 1.6;
@@ -1894,4 +1896,4 @@ span.icon > [class^="icon-"], span.icon > [class*=" icon-"] {
#header #revnumber{
color: #db4800;
-}
\ No newline at end of file
+}
diff --git a/src/spec/doc/core-differences-java.adoc b/src/spec/doc/core-differences-java.adoc
index 9a4bce77ab..acfe9585cc 100644
--- a/src/spec/doc/core-differences-java.adoc
+++ b/src/spec/doc/core-differences-java.adoc
@@ -296,11 +296,9 @@ are used very frequently and worthy of special treatment.
Primitives can be efficiently stored and manipulated but can't be used in all contexts where an object could be used.
Luckily, Java auto boxes and unboxes primitives when they are passed as parameters or used as return types:
-// a few shell blocks use "ruby" code style as it is more forgiving than Java or Groovy
-// it's not straight code after all, but might as well be a little pretty
[source,java]
----
-public class Main {
+public class Main { // Java
float f1 = 1.0f;
Float f2 = 2.0f;
@@ -348,12 +346,12 @@ Here is a little example using Java trying to (incorrectly for Java) dereference
[source,java]
----
-class Main {
+public class Main { // Java
public float z1 = 0.0f;
public static void main(String[] args){
- new Main().z1.equals(1.0f); // DOES NOT COMPILE, Cannot resolve method 'equals(float)'
+ new Main().z1.equals(1.0f); // DOESN'T COMPILE, error: float cannot be dereferenced
}
}
----
@@ -472,29 +470,30 @@ https://docs.oracle.com/javase/specs/jls/se7/html/jls-5.html[conversions].
Groovy expands greatly on this.
+[%autowidth]
[cols=">2s,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a,^1a"]
.Groovy Conversions
|=================================================================================================================================================================================================================
| 18+|*Converts to*
-| Converts from | *boolean* | *Boolean* | *byte* | *Byte* | *short* | *Short* | *char* | *Character* | *int* | *Integer* | *long* | *Long* | *BigInteger* | *float* | *Float* | *double* | *Double* | *BigDecimal*
-| boolean | - | B | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N
-| Boolean | B | - | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N
-| byte | T | T | - | B | Y | Y | Y | D | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
-| Byte | T | T | B | - | Y | Y | Y | D | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
-| short | T | T | D | D | - | B | Y | D | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
-| Short | T | T | D | T | B | - | Y | D | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
-| char | T | T | Y | D | Y | D | - | D | Y | D | Y | D | D | Y | D | Y | D | D
-| Character | T | T | D | D | D | D | D | - | D | D | D | D | D | D | D | D | D | D
-| int | T | T | D | D | D | D | Y | D | - | B | Y | Y | Y | Y | Y | Y | Y | Y
-| Integer | T | T | D | D | D | D | Y | D | B | - | Y | Y | Y | Y | Y | Y | Y | Y
-| long | T | T | D | D | D | D | Y | D | D | D | - | B | Y | T | T | T | T | Y
-| Long | T | T | D | D | D | T | Y | D | D | T | B | - | Y | T | T | T | T | Y
-| BigInteger | T | T | D | D | D | D | D | D | D | D | D | D | - | D | D | D | D | T
-| float | T | T | D | D | D | D | T | D | D | D | D | D | D | - | B | Y | Y | Y
-| Float | T | T | D | T | D | T | T | D | D | T | D | T | D | B | - | Y | Y | Y
-| double | T | T | D | D | D | D | T | D | D | D | D | D | D | D | D | - | B | Y
-| Double | T | T | D | T | D | T | T | D | D | T | D | T | D | D | T | B | - | Y
-| BigDecimal | T | T | D | D | D | D | D | D | D | D | D | D | D | T | D | T | D | -
+| Converts from |[.rotate]`boolean` |[.rotate]`Boolean` |[.rotate]`byte` |[.rotate]`Byte` |[.rotate]`short` |[.rotate]`Short` |[.rotate]`char` |[.rotate]`Character` |[.rotate]`int` |[.rotate]`Integer` |[.rotate]`long` |[.rotate]`Long` |[.rotate]`BigInteger` |[.rotate]`float` |[.rotate]`Float` |[.rotate]`double` |[.rotate]`Double` |[.rotate]`BigDecimal`
+| `boolean` | - | B | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N
+| `Boolean` | B | - | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N | N
+| `byte` | T | T | - | B | Y | Y | Y | D | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
+| `Byte` | T | T | B | - | Y | Y | Y | D | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
+| `short` | T | T | D | D | - | B | Y | D | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
+| `Short` | T | T | D | T | B | - | Y | D | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y
+| `char` | T | T | Y | D | Y | D | - | D | Y | D | Y | D | D | Y | D | Y | D | D
+| `Character` | T | T | D | D | D | D | D | - | D | D | D | D | D | D | D | D | D | D
+| `int` | T | T | D | D | D | D | Y | D | - | B | Y | Y | Y | Y | Y | Y | Y | Y
+| `Integer` | T | T | D | D | D | D | Y | D | B | - | Y | Y | Y | Y | Y | Y | Y | Y
+| `long` | T | T | D | D | D | D | Y | D | D | D | - | B | Y | T | T | T | T | Y
+| `Long` | T | T | D | D | D | T | Y | D | D | T | B | - | Y | T | T | T | T | Y
+| `BigInteger` | T | T | D | D | D | D | D | D | D | D | D | D | - | D | D | D | D | T
+| `float` | T | T | D | D | D | D | T | D | D | D | D | D | D | - | B | Y | Y | Y
+| `Float` | T | T | D | T | D | T | T | D | D | T | D | T | D | B | - | Y | Y | Y
+| `double` | T | T | D | D | D | D | T | D | D | D | D | D | D | D | D | - | B | Y
+| `Double` | T | T | D | T | D | T | T | D | D | T | D | T | D | D | T | B | - | Y
+| `BigDecimal` | T | T | D | D | D | D | D | D | D | D | D | D | D | T | D | T | D | -
|=================================================================================================================================================================================================================
* 'Y' indicates a conversion Groovy can make +
* 'D' indicates a conversion Groovy can make when compiled dynamically or explicitly cast +