Reduce parenthesis prevalence

examples/plugins/csv/src/generated/java/com/helger/jcodemodel/examples/plugin/csv/redirect/Redirected.java

@@ -17,6 +17,7 @@
 import com.helger.jcodemodel.IJFormatter;
 import com.helger.jcodemodel.JBlock;
 import com.helger.jcodemodel.JCatchBlock;
+import com.helger.jcodemodel.JOp;
 import com.helger.jcodemodel.vars.JCatchFormalParameter;
 
 public class Redirected {
@@ -73,6 +74,10 @@ public void generate(IJFormatter arg0) {
         jCatchBlock.generate(arg0);
     }
 
+    public JOp.Precedence operatorPrecedence() {
+        return jCatchBlock.operatorPrecedence();
+    }
+
     public JCatchFormalParameter param() {
         return jCatchBlock.param();
     }

examples/pom.xml

@@ -28,6 +28,7 @@
   <description>POM module for all the examples modules</description>
 
   <modules>
+    <module>settings</module>
     <module>plugins</module>
   </modules>
 

examples/settings/example-settings.json

@@ -0,0 +1,68 @@
+{
+  "indent" : {
+    "string" : "    ",
+    "tabSize" : 4
+  },
+  "parentheses" : {
+    "global" : "REQUIRED"
+  },
+  "wrap" : {
+    "lineWidth" : 80,
+    "disabled" : false,
+    "catchClause" : {
+      "types" : {
+        "condition" : "NEVER",
+        "indent" : 1,
+        "wrapAfterSep" : true
+      }
+    },
+    "forLoop" : {
+      "init" : {
+        "condition" : "NEVER",
+        "indent" : 1,
+        "wrapAfterSep" : true
+      }
+    },
+    "method" : {
+      "type" : {
+        "condition" : "NEVER",
+        "indent" : 1
+      },
+      "name" : {
+        "condition" : "NEVER",
+        "indent" : 1
+      },
+      "params" : {
+        "condition" : "PAST3",
+        "indent" : 1,
+        "wrapAfterSep" : true
+      },
+      "bracket" : {
+        "condition" : "NEVER",
+        "indent" : 0
+      },
+      "args" : {
+        "condition" : "PAST3",
+        "indent" : 1,
+        "wrapAfterSep" : true
+      }
+    },
+    "variables" : {
+      "array" : {
+        "condition" : "REQUIRED",
+        "indent" : 1,
+        "wrapAfterSep" : true
+      },
+      "block" : {
+        "condition" : "REQUIRED",
+        "indent" : 1,
+        "wrapAfterSep" : true
+      },
+      "field" : {
+        "condition" : "REQUIRED",
+        "indent" : 1,
+        "wrapAfterSep" : true
+      }
+    }
+  }
+}

examples/settings/example-settings.yaml

@@ -0,0 +1,49 @@
+indent:
+  string: "    "
+  tabSize: 4
+parentheses:
+  global: "REQUIRED"
+wrap:
+  lineWidth: 80
+  disabled: false
+  catchClause:
+    types:
+      condition: "NEVER"
+      indent: 1
+      wrapAfterSep: true
+  forLoop:
+    init:
+      condition: "NEVER"
+      indent: 1
+      wrapAfterSep: true
+  method:
+    type:
+      condition: "NEVER"
+      indent: 1
+    name:
+      condition: "NEVER"
+      indent: 1
+    params:
+      condition: "PAST3"
+      indent: 1
+      wrapAfterSep: true
+    bracket:
+      condition: "NEVER"
+      indent: 0
+    args:
+      condition: "PAST3"
+      indent: 1
+      wrapAfterSep: true
+  variables:
+    array:
+      condition: "REQUIRED"
+      indent: 1
+      wrapAfterSep: true
+    block:
+      condition: "REQUIRED"
+      indent: 1
+      wrapAfterSep: true
+    field:
+      condition: "REQUIRED"
+      indent: 1
+      wrapAfterSep: true

examples/settings/pom.xml

@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- Licensed 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. -->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <parent>
+    <groupId>com.helger.jcodemodel</groupId>
+    <artifactId>examples</artifactId>
+    <version>4.3.1-SNAPSHOT</version>
+  </parent>
+  <groupId>com.helger.jcodemodel.examples</groupId>
+  <artifactId>settings</artifactId>
+  <name>LIB Settings Examples</name>
+  <description>shows setting examples</description>
+
+  <properties>
+    <jackson.version>2.20.1</jackson.version>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.fasterxml.jackson.dataformat</groupId>
+      <artifactId>jackson-dataformat-yaml</artifactId>
+      <version>${jackson.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>com.helger.jcodemodel.plugin.generators</groupId>
+      <artifactId>json</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+  </dependencies>
+</project>

examples/settings/src/test/java/com/helger/jcodemodel/example/settings/ExportSettingsTest.java

@@ -0,0 +1,60 @@
+package com.helger.jcodemodel.example.settings;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.UncheckedIOException;
+
+import org.junit.Test;
+
+import com.fasterxml.jackson.core.util.DefaultIndenter;
+import com.fasterxml.jackson.core.util.DefaultPrettyPrinter;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationFeature;
+import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
+import com.fasterxml.jackson.dataformat.yaml.YAMLGenerator.Feature;
+import com.helger.jcodemodel.writer.FormatterSettings;
+
+/// Actually not a test, but export the default formatter settings so people
+/// have an idea of the settings available.
+/// The yaml and json files are exported at the project root.
+public class ExportSettingsTest {
+
+  @Test
+  public void writeYaml() {
+    FormatterSettings export = new FormatterSettings();
+
+    YAMLFactory f =
+        new YAMLFactory()
+            .disable(Feature.WRITE_DOC_START_MARKER);
+    ObjectMapper om = new ObjectMapper(f);
+
+    File out = new File("example-settings.yaml");
+    try (FileWriter writer = new FileWriter(out)) {
+      om.writer().writeValue(writer, export);
+    } catch (IOException e) {
+      throw new UncheckedIOException(e);
+    }
+  }
+
+  @Test
+  public void writeJson() {
+    FormatterSettings export = new FormatterSettings();
+
+    DefaultPrettyPrinter prettyPrinter =
+        new DefaultPrettyPrinter()
+        .withObjectIndenter(new DefaultIndenter().withLinefeed("\n"));
+    ObjectMapper om =
+        new ObjectMapper()
+            .setDefaultPrettyPrinter(prettyPrinter)
+            .enable(SerializationFeature.INDENT_OUTPUT);
+
+    File out = new File("example-settings.json");
+    try (FileWriter writer = new FileWriter(out)) {
+      om.writer().writeValue(writer, export);
+    } catch (IOException e) {
+      throw new UncheckedIOException(e);
+    }
+  }
+
+}

jcodemodel/src/main/java/com/helger/jcodemodel/IJExpression.java

@@ -807,4 +807,5 @@ default JCast castTo (@NonNull final AbstractJType aType)
   {
     return JExpr.cast (aType, this);
   }
+
 }

jcodemodel/src/main/java/com/helger/jcodemodel/IJGenerable.java

@@ -42,10 +42,28 @@
 
 import org.jspecify.annotations.NonNull;
 
+import com.helger.jcodemodel.JOp.Precedence;
+
 /**
  * Common interface for code components that can generate uses of themselves.
  */
 public interface IJGenerable extends IJObject
 {
   void generate (@NonNull IJFormatter f);
+
+  /// Indicates the operator precedence at which an operator addition can change the meaning of
+  /// this. Used to check the need for parentheses.
+  ///
+  /// For example, an "a+b*c" element would return the precedence of "+", and any operator with
+  /// an higher precedence could break it : a "++" operator would require parentheses since
+  /// "a+b*c++" is not the same as "(a+b*c)++"
+  ///
+  /// Most elements are not operator-sensitive so the default is the max precedence (token). For
+  /// example method call( "myFunction()" )
+  ///
+  /// @return the lowest operator precedence.
+  default JOp.Precedence operatorPrecedence ()
+  {
+    return Precedence.TOKEN;
+  }
 }

jcodemodel/src/main/java/com/helger/jcodemodel/JArrayCompRef.java

@@ -46,6 +46,7 @@
 
 import com.helger.base.enforce.ValueEnforcer;
 import com.helger.base.equals.EqualsHelper;
+import com.helger.jcodemodel.JOp.Precedence;
 
 /**
  * array component reference.
@@ -92,7 +93,30 @@ public IJExpression index ()
 
   public void generate (@NonNull final IJFormatter f)
   {
-    f.generable (m_aArray).print ('[').generable (m_aIndex).print (']');
+    boolean parentheses = true;
+    switch (f.settings ().parentheses.global)
+    {
+      case ALWAYS ->
+      {
+        parentheses = true;
+      }
+      case NOTOKEN ->
+      {
+        parentheses = m_aArray.operatorPrecedence () != Precedence.TOKEN;
+      }
+      case REQUIRED ->
+      {
+        parentheses = Precedence.DEREF.higherThan (m_aArray.operatorPrecedence ());
+      }
+      default -> throw new IllegalArgumentException ("Unexpected value: " + f.settings ().parentheses.global);
+    }
+
+    if (parentheses)
+      f.print ('(');
+    f.generable (m_aArray);
+    if (parentheses)
+      f.print (')');
+    f.print ('[').generable (m_aIndex).print (']');
   }
 
   @Override
@@ -111,4 +135,10 @@ public int hashCode ()
   {
     return getHashCode (this, m_aArray, m_aIndex);
   }
+
+  @Override
+  public Precedence operatorPrecedence ()
+  {
+    return Precedence.DEREF;
+  }
 }

jcodemodel/src/main/java/com/helger/jcodemodel/JAssignment.java

@@ -45,6 +45,7 @@
 import org.jspecify.annotations.NonNull;
 
 import com.helger.base.equals.EqualsHelper;
+import com.helger.jcodemodel.JOp.Precedence;
 
 /**
  * Assignment statements, which are also expressions.
@@ -119,7 +120,31 @@ public String opFull ()
 
   public void generate (@NonNull final IJFormatter f)
   {
-    f.generable (m_aLhs).print (opFull ()).generable (m_aRhs);
+    // only right side may need parentheses
+    boolean parentheses = true;
+    switch (f.settings ().parentheses.global)
+    {
+      case ALWAYS ->
+      {
+        parentheses = true;
+      }
+      case NOTOKEN ->
+      {
+        parentheses = m_aRhs.operatorPrecedence () != Precedence.TOKEN;
+      }
+      case REQUIRED ->
+      {
+        // basically only lambdas need to be parenthesized
+        parentheses = Precedence.ASSIGNMENT.higherThan (m_aRhs.operatorPrecedence ());
+      }
+      default -> throw new IllegalArgumentException ("Unexpected value: " + f.settings ().parentheses.global);
+    }
+    f.generable (m_aLhs).print (opFull ());
+    if (parentheses)
+      f.print ('(');
+    f.generable (m_aRhs);
+    if (parentheses)
+      f.print (')');
   }
 
   public void state (@NonNull final IJFormatter f)
@@ -145,4 +170,10 @@ public int hashCode ()
   {
     return getHashCode (this, m_aLhs, m_aRhs, m_sOperator);
   }
+
+  @Override
+  public Precedence operatorPrecedence ()
+  {
+    return Precedence.ASSIGNMENT;
+  }
 }