FormatterExplicitEncoding.java
/*******************************************************************************
* Copyright (c) 2021 Carsten Hammer.
*
* This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-2.0/
*
* SPDX-License-Identifier: EPL-2.0
*
* Contributors:
* Carsten Hammer
*******************************************************************************/
package org.sandbox.jdt.internal.corext.fix.helper;
import java.io.File;
import java.io.OutputStream;
import java.util.Formatter;
import java.util.List;
import java.util.Locale;
import java.util.Set;
import org.eclipse.text.edits.TextEditGroup;
import org.eclipse.jdt.core.dom.AST;
import org.eclipse.jdt.core.dom.ASTNode;
import org.eclipse.jdt.core.dom.ClassInstanceCreation;
import org.eclipse.jdt.core.dom.CompilationUnit;
import org.eclipse.jdt.core.dom.IMethodBinding;
import org.eclipse.jdt.core.dom.ITypeBinding;
import org.eclipse.jdt.core.dom.MethodInvocation;
import org.eclipse.jdt.core.dom.StringLiteral;
import org.eclipse.jdt.core.dom.rewrite.ASTRewrite;
import org.eclipse.jdt.core.dom.rewrite.ImportRewrite;
import org.eclipse.jdt.core.dom.rewrite.ListRewrite;
import org.sandbox.jdt.internal.common.HelperVisitorFactory;
import org.sandbox.jdt.internal.common.ReferenceHolder;
import org.eclipse.jdt.internal.corext.dom.ASTNodeFactory;
import org.eclipse.jdt.internal.corext.dom.ASTNodes;
import org.eclipse.jdt.internal.corext.fix.CompilationUnitRewriteOperationsFixCore.CompilationUnitRewriteOperation;
import org.sandbox.jdt.internal.corext.fix.UseExplicitEncodingFixCore;
import org.eclipse.jdt.internal.corext.refactoring.structure.CompilationUnitRewrite;
import org.eclipse.jdt.internal.corext.util.JavaModelUtil;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.jdt.internal.core.manipulation.JavaManipulationPlugin;
/**
* Java 10
*
* Find: new java.util.Formatter(new File(), String cs) throws UnsupportedEncodingException
*
* Rewrite: new java.util.Formatter(new File(), Charset cs, Locale.getDefault())
*
* Find: new java.util.Formatter(new File(), String cs, new java.util.Locale())
*
* Rewrite: new java.util.Formatter(new File(), Charset cs, new java.util.Locale())
*
* Find: new java.util.Formatter(new java.io.OutputStream(), String cs)
*
* Rewrite: new java.util.Formatter(new java.io.OutputStream(), Charset cs, Locale.getDefault())
*
* Find: new java.util.Formatter(new java.io.OutputStream(), String cs, new java.util.Locale())
*
* Rewrite: new java.util.Formatter(new java.io.OutputStream(), Charset cs, new java.util.Locale())
*
* Find: new java.util.Formatter(new String(), String cs)
*
* Rewrite: new java.util.Formatter(new String(), Charset cs, Locale.getDefault())
*
* Find: new java.util.Formatter(new String(), String cs, new java.util.Locale())
*
* Rewrite: new java.util.Formatter(new String(), Charset cs, new java.util.Locale())
*
* Find: new java.util.Formatter(new File())
*
* Rewrite: new java.util.Formatter(new File(), Charset.defaultCharset(), Locale.getDefault())
*
* Find: new java.util.Formatter(fileName)
*
* Rewrite: new java.util.Formatter(fileName, Charset.defaultCharset(), Locale.getDefault())
*
* Find: new java.util.Formatter(outputStream)
*
* Rewrite: new java.util.Formatter(outputStream, Charset.defaultCharset(), Locale.getDefault())
*
* Note: The Formatter constructors accepting Charset are all 3-argument constructors
* (File/String/OutputStream, Charset, Locale) and were introduced in Java 10.
* There is no 2-argument Formatter(File/String/OutputStream, Charset) constructor.
* Formatter(Appendable), Formatter(Locale), and Formatter(PrintStream) do NOT involve
* encoding and are intentionally NOT handled.
* See https://docs.oracle.com/en/java/javase/22/docs/api/java.base/java/util/Formatter.html
*
*/
public class FormatterExplicitEncoding extends AbstractExplicitEncoding<ClassInstanceCreation> {
@Override
public void find(UseExplicitEncodingFixCore fixcore, CompilationUnit compilationUnit, Set<CompilationUnitRewriteOperation> operations, Set<ASTNode> nodesprocessed, ChangeBehavior cb) {
if (!JavaModelUtil.is10OrHigher(compilationUnit.getJavaElement().getJavaProject())) {
/**
* For Java 9 and older just do nothing.
* The Formatter constructors accepting Charset were introduced in Java 10.
*/
return;
}
ReferenceHolder<ASTNode, Object> datah= ReferenceHolder.createForNodes();
HelperVisitorFactory.forClassInstanceCreation(Formatter.class)
.in(compilationUnit)
.excluding(nodesprocessed)
.processEach(datah, (visited, holder) -> processFoundNode(fixcore, operations, cb, visited, holder));
}
private static boolean processFoundNode(UseExplicitEncodingFixCore fixcore,
Set<CompilationUnitRewriteOperation> operations,
ChangeBehavior cb,
ClassInstanceCreation visited,
ReferenceHolder<ASTNode, Object> holder) {
List<ASTNode> arguments= visited.arguments();
switch (arguments.size()) {
case 2:
case 3:
if (arguments.get(1) instanceof StringLiteral) {
StringLiteral argString= (StringLiteral) arguments.get(1);
String encodingKey= argString.getLiteralValue().toUpperCase(java.util.Locale.ROOT);
if (ENCODINGS.contains(encodingKey)) {
NodeData nd= new NodeData(true, argString, ENCODING_MAP.get(encodingKey));
holder.put(visited, nd);
operations.add(fixcore.rewrite(visited, cb, holder));
}
}
break;
case 1:
if (isEncodingRelevantSingleArgConstructor(visited)) {
NodeData nd2= new NodeData(false, visited, null);
holder.put(visited, nd2);
operations.add(fixcore.rewrite(visited, cb, holder));
}
break;
default:
break;
}
return false;
}
/**
* Checks whether a 1-argument Formatter constructor uses the platform default encoding
* and should be migrated.
*
* <p>Only these 1-arg constructors use the default encoding:
* <ul>
* <li>{@code Formatter(String fileName)} — uses default charset</li>
* <li>{@code Formatter(File file)} — uses default charset</li>
* <li>{@code Formatter(OutputStream os)} — uses default charset</li>
* </ul>
*
* <p>These 1-arg constructors do NOT involve encoding and must be skipped:
* <ul>
* <li>{@code Formatter(Appendable a)}</li>
* <li>{@code Formatter(Locale l)}</li>
* <li>{@code Formatter(PrintStream ps)}</li>
* </ul>
*
* @param visited the ClassInstanceCreation node
* @return true if this is an encoding-relevant 1-arg Formatter constructor
*/
private static boolean isEncodingRelevantSingleArgConstructor(ClassInstanceCreation visited) {
IMethodBinding binding= visited.resolveConstructorBinding();
if (binding == null) {
return false;
}
ITypeBinding[] paramTypes= binding.getParameterTypes();
if (paramTypes.length != 1) {
return false;
}
String paramTypeName= paramTypes[0].getQualifiedName();
return File.class.getCanonicalName().equals(paramTypeName)
|| String.class.getCanonicalName().equals(paramTypeName)
|| OutputStream.class.getCanonicalName().equals(paramTypeName);
}
@Override
public void rewrite(UseExplicitEncodingFixCore upp, final ClassInstanceCreation visited, final CompilationUnitRewrite cuRewrite,
TextEditGroup group, ChangeBehavior cb, ReferenceHolder<ASTNode, Object> data) {
ASTRewrite rewrite= cuRewrite.getASTRewrite();
AST ast= cuRewrite.getRoot().getAST();
NodeData nodedata= (NodeData) data.get(visited);
ASTNode callToCharsetDefaultCharset= cb.computeCharsetASTNode(cuRewrite, ast, nodedata.encoding(),getCharsetConstants());
/**
* Register encoding replacement BEFORE removing exception handling.
* removeUnsupportedEncodingException may call simplifyEmptyTryStatement
* which uses createMoveTarget to move statements out of the try block.
* replaceAndRemoveNLS fails silently on nodes that have already been
* marked as move targets, so the replacement must be registered first.
*/
ListRewrite listRewrite= rewrite.getListRewrite(visited, ClassInstanceCreation.ARGUMENTS_PROPERTY);
boolean tryAlreadyUnwrapped= false;
if (nodedata.replace()) {
if (visited.arguments().size() == 2) {
/**
* 2-arg case: Formatter(X, String) -> Formatter(X, Charset, Locale.getDefault())
* There is no Formatter(X, Charset) 2-arg constructor.
* All Charset constructors are 3-arg: Formatter(X, Charset, Locale).
*
* IMPORTANT: Cannot use replaceAndRemoveNLS here because it conflicts
* with ListRewrite operations (insertLast silently fails).
* Use listRewrite.replace() + listRewrite.insertLast() instead.
* See https://github.com/eclipse-jdt/eclipse.jdt.ui/issues/121
*/
listRewrite.replace(nodedata.visited(), callToCharsetDefaultCharset, group);
listRewrite.insertLast(createLocaleGetDefault(cuRewrite, ast), group);
} else {
/**
* 3-arg case: Formatter(X, String, Locale) -> Formatter(X, Charset, Locale)
* Only replace needed, no insertion.
*/
tryAlreadyUnwrapped= replaceArgumentAndRemoveNLS(rewrite, nodedata.visited(), callToCharsetDefaultCharset, group, cuRewrite);
}
} else {
/**
* 1-arg case: Formatter(X) -> Formatter(X, Charset.defaultCharset(), Locale.getDefault())
* There is no Formatter(X, Charset) 2-arg constructor.
*/
listRewrite.insertLast(callToCharsetDefaultCharset, group);
listRewrite.insertLast(createLocaleGetDefault(cuRewrite, ast), group);
}
if (!tryAlreadyUnwrapped) {
removeUnsupportedEncodingException(visited, group, rewrite, cuRewrite.getImportRemover());
}
}
/**
* Create call to Locale.getDefault()
*
* @param cuRewrite CompilationUnitRewrite
* @param ast AST
* @return MethodInvocation that returns Locale.getDefault()
*/
private static MethodInvocation createLocaleGetDefault(final CompilationUnitRewrite cuRewrite, AST ast) {
ImportRewrite importRewrite= cuRewrite.getImportRewrite();
importRewrite.addImport(Locale.class.getCanonicalName());
MethodInvocation localeCall= ast.newMethodInvocation();
localeCall.setExpression(ASTNodeFactory.newName(ast, Locale.class.getSimpleName()));
localeCall.setName(ast.newSimpleName("getDefault")); //$NON-NLS-1$
return localeCall;
}
@Override
public String getPreview(boolean afterRefactoring, ChangeBehavior cb) {
if (afterRefactoring) {
return "Formatter r=new java.util.Formatter(out, " + cb.computeCharsetforPreview() + ", Locale.getDefault());\n"; //$NON-NLS-1$ //$NON-NLS-2$
}
return "Formatter r=new java.util.Formatter(out);\n"; //$NON-NLS-1$
}
@Override
public String toString() {
return "new java.util.Formatter(out)"; //$NON-NLS-1$
}
}