diff options
Diffstat (limited to 'javaparser-core/src/main/java/com/github/javaparser/ast/validator/chunks/VarValidator.java')
-rw-r--r-- | javaparser-core/src/main/java/com/github/javaparser/ast/validator/chunks/VarValidator.java | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/javaparser-core/src/main/java/com/github/javaparser/ast/validator/chunks/VarValidator.java b/javaparser-core/src/main/java/com/github/javaparser/ast/validator/chunks/VarValidator.java new file mode 100644 index 000000000..19357e83c --- /dev/null +++ b/javaparser-core/src/main/java/com/github/javaparser/ast/validator/chunks/VarValidator.java @@ -0,0 +1,93 @@ +package com.github.javaparser.ast.validator.chunks; + +import com.github.javaparser.ast.Node; +import com.github.javaparser.ast.body.Parameter; +import com.github.javaparser.ast.body.VariableDeclarator; +import com.github.javaparser.ast.expr.ArrayCreationExpr; +import com.github.javaparser.ast.expr.LambdaExpr; +import com.github.javaparser.ast.expr.NullLiteralExpr; +import com.github.javaparser.ast.expr.VariableDeclarationExpr; +import com.github.javaparser.ast.stmt.ExpressionStmt; +import com.github.javaparser.ast.stmt.ForStmt; +import com.github.javaparser.ast.stmt.ForeachStmt; +import com.github.javaparser.ast.type.VarType; +import com.github.javaparser.ast.validator.ProblemReporter; +import com.github.javaparser.ast.validator.TypedValidator; + +import java.util.Optional; + +public class VarValidator implements TypedValidator<VarType> { + private boolean varAllowedInLambdaParameters; + + public VarValidator(boolean varAllowedInLambdaParameters) { + this.varAllowedInLambdaParameters = varAllowedInLambdaParameters; + } + + @Override + public void accept(VarType node, ProblemReporter reporter) { + // All allowed locations are within a VariableDeclaration inside a VariableDeclarationExpr inside something else. + Optional<VariableDeclarator> variableDeclarator = node.findParent(VariableDeclarator.class); + if (!variableDeclarator.isPresent()) { + // Java 11's var in lambda's + if (varAllowedInLambdaParameters) { + boolean valid = node + .findParent(Parameter.class) + .flatMap(Node::getParentNode) + .map((Node p) -> p instanceof LambdaExpr).orElse(false); + if (valid) { + return; + } + } + reportIllegalPosition(node, reporter); + return; + } + variableDeclarator.ifPresent(vd -> { + Optional<Node> variableDeclarationExpr = vd.getParentNode(); + if (!variableDeclarationExpr.isPresent()) { + reportIllegalPosition(node, reporter); + return; + } + variableDeclarationExpr.ifPresent(vdeNode -> { + if (!(vdeNode instanceof VariableDeclarationExpr)) { + reportIllegalPosition(node, reporter); + return; + } + VariableDeclarationExpr vde = (VariableDeclarationExpr) vdeNode; + if (vde.getVariables().size() > 1) { + reporter.report(vde, "\"var\" only takes a single variable."); + } + Optional<Node> container = vdeNode.getParentNode(); + if (!container.isPresent()) { + reportIllegalPosition(node, reporter); + return; + } + container.ifPresent(c -> { + boolean positionIsFine = c instanceof ForStmt || c instanceof ForeachStmt || c instanceof ExpressionStmt; + if (!positionIsFine) { + reportIllegalPosition(node, reporter); + } + // A local variable declaration ends up inside an ExpressionStmt. + if (c instanceof ExpressionStmt) { + if (!vd.getInitializer().isPresent()) { + reporter.report(node, "\"var\" needs an initializer."); + } + vd.getInitializer().ifPresent(initializer -> { + if (initializer instanceof NullLiteralExpr) { + reporter.report(node, "\"var\" cannot infer type from just null."); + } + if (initializer instanceof ArrayCreationExpr) { + reporter.report(node, "\"var\" cannot infer array types."); + } + }); + + } + }); + }); + }); + + } + + private void reportIllegalPosition(VarType n, ProblemReporter reporter) { + reporter.report(n, "\"var\" is not allowed here."); + } +} |