db2 sql parser support sequence expr. fixed issue #1323

src/main/java/com/alibaba/druid/sql/ast/expr/SQLSequenceExpr.java

@@ -0,0 +1,79 @@
+package com.alibaba.druid.sql.ast.expr;
+
+import com.alibaba.druid.sql.ast.SQLExprImpl;
+import com.alibaba.druid.sql.ast.SQLName;
+import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+
+public class SQLSequenceExpr extends SQLExprImpl {
+
+    private SQLName  sequence;
+    private Function function;
+
+    public SQLSequenceExpr(){
+
+    }
+
+    public SQLSequenceExpr(SQLName sequence, Function function){
+        this.sequence = sequence;
+        this.function = function;
+    }
+
+    @Override
+    protected void accept0(SQLASTVisitor visitor) {
+        if (visitor.visit(this)) {
+            acceptChild(visitor, sequence);
+        }
+        visitor.endVisit(this);
+    }
+
+    public static enum Function {
+                                 NextVal("NEXTVAL"), CurrVal("CURRVAL"), PrevVal("PREVVAL");
+
+        public final String name;
+        public final String name_lcase;
+
+        private Function(String name){
+            this.name = name;
+            this.name_lcase = name.toLowerCase();
+        }
+    }
+
+    public SQLName getSequence() {
+        return sequence;
+    }
+
+    public void setSequence(SQLName sequence) {
+        this.sequence = sequence;
+    }
+
+    public Function getFunction() {
+        return function;
+    }
+
+    public void setFunction(Function function) {
+        this.function = function;
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((function == null) ? 0 : function.hashCode());
+        result = prime * result + ((sequence == null) ? 0 : sequence.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) return true;
+        if (obj == null) return false;
+        if (getClass() != obj.getClass()) return false;
+        SQLSequenceExpr other = (SQLSequenceExpr) obj;
+        if (function != other.function) return false;
+        if (sequence == null) {
+            if (other.sequence != null) return false;
+        } else if (!sequence.equals(other.sequence)) return false;
+        return true;
+    }
+
+}