svn commit: r826815 - /hadoop/pig/trunk/src/org/apache/pig/impl/logicalLayer/validators/SchemaAliasVisitor.java

[da...@apache.org]

Author: daijy
Date: Mon Oct 19 21:15:44 2009
New Revision: 826815

URL: http://svn.apache.org/viewvc?rev=826815&view=rev
Log:
PIG-644: Duplicate column names in foreach do not throw parser error

Added:
    hadoop/pig/trunk/src/org/apache/pig/impl/logicalLayer/validators/SchemaAliasVisitor.java

Added: hadoop/pig/trunk/src/org/apache/pig/impl/logicalLayer/validators/SchemaAliasVisitor.java
URL: http://svn.apache.org/viewvc/hadoop/pig/trunk/src/org/apache/pig/impl/logicalLayer/validators/SchemaAliasVisitor.java?rev=826815&view=auto
==============================================================================
--- hadoop/pig/trunk/src/org/apache/pig/impl/logicalLayer/validators/SchemaAliasVisitor.java (added)
+++ hadoop/pig/trunk/src/org/apache/pig/impl/logicalLayer/validators/SchemaAliasVisitor.java Mon Oct 19 21:15:44 2009
@@ -0,0 +1,137 @@
+package org.apache.pig.impl.logicalLayer.validators;
+
+import org.apache.pig.PigException;
+import org.apache.pig.impl.logicalLayer.FrontendException;
+import org.apache.pig.impl.logicalLayer.LOCogroup;
+import org.apache.pig.impl.logicalLayer.LOCross;
+import org.apache.pig.impl.logicalLayer.LODistinct;
+import org.apache.pig.impl.logicalLayer.LOFilter;
+import org.apache.pig.impl.logicalLayer.LOForEach;
+import org.apache.pig.impl.logicalLayer.LOJoin;
+import org.apache.pig.impl.logicalLayer.LOLimit;
+import org.apache.pig.impl.logicalLayer.LOLoad;
+import org.apache.pig.impl.logicalLayer.LOSort;
+import org.apache.pig.impl.logicalLayer.LOSplit;
+import org.apache.pig.impl.logicalLayer.LOSplitOutput;
+import org.apache.pig.impl.logicalLayer.LOStore;
+import org.apache.pig.impl.logicalLayer.LOStream;
+import org.apache.pig.impl.logicalLayer.LOUnion;
+import org.apache.pig.impl.logicalLayer.LOVisitor;
+import org.apache.pig.impl.logicalLayer.LogicalOperator;
+import org.apache.pig.impl.logicalLayer.LogicalPlan;
+import org.apache.pig.impl.logicalLayer.schema.Schema;
+import org.apache.pig.impl.plan.DepthFirstWalker;
+import org.apache.pig.impl.plan.PlanValidationException;
+
+public class SchemaAliasVisitor extends LOVisitor {
+
+    public SchemaAliasVisitor(LogicalPlan plan) {
+        super(plan, new DepthFirstWalker<LogicalOperator, LogicalPlan>(plan));
+    }
+
+    /***
+     * The logic here is to check if we have duplicate alias in each schema
+     */
+    protected void validate(LogicalOperator lo) throws PlanValidationException {
+        try {
+            Schema schema = lo.getSchema();
+            if (schema != null) {
+                for (int i = 0; i < schema.size(); i++)
+                    for (int j = i + 1; j < schema.size(); j++) {
+                        if (schema.getField(i) != null
+                                && schema.getField(j) != null
+                                && schema.getField(i).alias.equals(schema
+                                        .getField(j).alias)) {
+                            int errCode = 1108;
+                            String msg = "Duplicate schema alias: "
+                                    + schema.getField(i).alias;
+                            if (lo.getAlias()!=null)
+                                msg = msg + " in \"" + lo.getAlias()+"\"";
+                            throw new PlanValidationException(msg, errCode,
+                                    PigException.INPUT);
+                        }
+                    }
+            }
+        } catch (PlanValidationException e) {
+            throw e;
+        } catch (FrontendException e) {
+            int errCode = 2201;
+            String msg = "Could not validate schema alias";
+            throw new PlanValidationException(msg, errCode, PigException.INPUT);
+        }
+    }
+
+    @Override
+    protected void visit(LOLoad load) throws PlanValidationException {
+        validate(load);
+    }
+
+    @Override
+    protected void visit(LOCogroup cogroup) throws PlanValidationException {
+        validate(cogroup);
+    }
+
+    @Override
+    protected void visit(LOCross cross) throws PlanValidationException {
+        validate(cross);
+    }
+
+    @Override
+    protected void visit(LODistinct distinct) throws PlanValidationException {
+        validate(distinct);
+    }
+
+    @Override
+    protected void visit(LOFilter filter) throws PlanValidationException {
+        validate(filter);
+    }
+
+    @Override
+    protected void visit(LOForEach foreach) throws PlanValidationException {
+        validate(foreach);
+    }
+
+    @Override
+    protected void visit(LOJoin join) throws PlanValidationException {
+        validate(join);
+    }
+
+    @Override
+    protected void visit(LOLimit limit) throws PlanValidationException {
+        validate(limit);
+    }
+
+    @Override
+    protected void visit(LOSort sort) throws PlanValidationException {
+        validate(sort);
+    }
+
+    @Override
+    protected void visit(LOSplit split) throws PlanValidationException {
+        validate(split);
+    }
+
+    @Override
+    protected void visit(LOSplitOutput splitoutput)
+            throws PlanValidationException {
+        validate(splitoutput);
+    }
+
+    @Override
+    protected void visit(LOStore store) throws PlanValidationException {
+        validate(store);
+        return;
+    }
+
+    @Override
+    protected void visit(LOStream stream) throws PlanValidationException {
+        validate(stream);
+        return;
+    }
+
+    @Override
+    protected void visit(LOUnion union) throws PlanValidationException {
+        validate(union);
+        return;
+    }
+}