fixes #450

Author: wumpz

README.md

@@ -60,6 +60,7 @@ Also I would like to know about needed examples or documentation stuff.
 
 ## Extensions in the latest SNAPSHOT version 2.1
 
+* support for **show** statment (API - change)
 * introduces Statement streaming support by **CCJSqlParserUtil.streamStatements**
 * improved nested bracket parsing performance by a large scale
 

src/main/java/net/sf/jsqlparser/statement/ShowColumnsStatement.java

@@ -0,0 +1,37 @@
+/*-
+ * #%L
+ * JSQLParser library
+ * %%
+ * Copyright (C) 2004 - 2019 JSQLParser
+ * %%
+ * Dual licensed under GNU LGPL 2.1 or Apache License 2.0
+ * #L%
+ */
+package net.sf.jsqlparser.statement;
+
+public class ShowColumnsStatement implements Statement {
+
+    private String tableName;
+
+    public ShowColumnsStatement(String tableName) {
+        this.tableName = tableName;
+    }
+
+    public String getTableName() {
+        return tableName;
+    }
+
+    public void setTableName(String tableName) {
+        this.tableName = tableName;
+    }
+
+    @Override
+    public String toString() {
+        return "SHOW COLUMNS FROM " + tableName;
+    }
+
+    @Override
+    public void accept(StatementVisitor statementVisitor) {
+        statementVisitor.visit(this);
+    }
+}

src/main/java/net/sf/jsqlparser/statement/ShowStatement.java

@@ -11,23 +11,23 @@
 
 public class ShowStatement implements Statement {
 
-    private String tableName;
+    private String name;
 
-    public ShowStatement(String tableName) {
-        this.tableName = tableName;
+    public ShowStatement(String name) {
+        this.name = name;
     }
 
-    public String getTableName() {
-        return tableName;
+    public String getName() {
+        return name;
     }
 
-    public void setTableName(String tableName) {
-        this.tableName = tableName;
+    public void setName(String name) {
+        this.name = name;
     }
 
     @Override
     public String toString() {
-        return "SHOW COLUMNS FROM " + tableName;
+        return "SHOW " + name;
     }
 
     @Override

src/main/java/net/sf/jsqlparser/statement/StatementVisitor.java

@@ -61,7 +61,7 @@ public interface StatementVisitor {
 
     void visit(SetStatement set);
 
-    void visit(ShowStatement set);
+    void visit(ShowColumnsStatement set);
 
     void visit(Merge merge);
 
@@ -78,4 +78,6 @@ public interface StatementVisitor {
     void visit(DescribeStatement describe);
 
     public void visit(ExplainStatement aThis);
+
+    public void visit(ShowStatement aThis);
 }

src/main/java/net/sf/jsqlparser/statement/StatementVisitorAdapter.java

@@ -112,7 +112,7 @@ public void visit(SetStatement set) {
     }
 
     @Override
-    public void visit(ShowStatement set) {
+    public void visit(ShowColumnsStatement set) {
     }
 
     @Override
@@ -147,4 +147,8 @@ public void visit(DescribeStatement describe) {
     @Override
     public void visit(ExplainStatement aThis) {
     }
+
+    @Override
+    public void visit(ShowStatement aThis) {
+    }
 }

src/main/java/net/sf/jsqlparser/util/TablesNamesFinder.java

@@ -88,6 +88,7 @@
 import net.sf.jsqlparser.statement.DescribeStatement;
 import net.sf.jsqlparser.statement.ExplainStatement;
 import net.sf.jsqlparser.statement.SetStatement;
+import net.sf.jsqlparser.statement.ShowColumnsStatement;
 import net.sf.jsqlparser.statement.ShowStatement;
 import net.sf.jsqlparser.statement.Statement;
 import net.sf.jsqlparser.statement.StatementVisitor;
@@ -733,7 +734,7 @@ public void visit(SetStatement set) {
     }
 
     @Override
-    public void visit(ShowStatement set) {
+    public void visit(ShowColumnsStatement set) {
         throw new UnsupportedOperationException(NOT_SUPPORTED_YET);
     }
 
@@ -851,4 +852,8 @@ public void visit(NextValExpression nextVal) {
     public void visit(CollateExpression col) {
         col.getLeftExpression().accept(this);
     }
+
+    @Override
+    public void visit(ShowStatement aThis) {
+    }
 }

src/main/java/net/sf/jsqlparser/util/deparser/ShowColumnsStatementDeParser.java

@@ -0,0 +1,33 @@
+/*-
+ * #%L
+ * JSQLParser library
+ * %%
+ * Copyright (C) 2004 - 2019 JSQLParser
+ * %%
+ * Dual licensed under GNU LGPL 2.1 or Apache License 2.0
+ * #L%
+ */
+package net.sf.jsqlparser.util.deparser;
+
+import net.sf.jsqlparser.statement.ShowColumnsStatement;
+
+public class ShowColumnsStatementDeParser {
+
+    protected StringBuilder buffer;
+
+    public ShowColumnsStatementDeParser(StringBuilder buffer) {
+        this.buffer = buffer;
+    }
+
+    public StringBuilder getBuffer() {
+        return buffer;
+    }
+
+    public void setBuffer(StringBuilder buffer) {
+        this.buffer = buffer;
+    }
+
+    public void deParse(ShowColumnsStatement show) {
+        buffer.append("SHOW COLUMNS FROM ").append(show.getTableName());
+    }
+}

src/main/java/net/sf/jsqlparser/util/deparser/ShowStatementDeParser.java

@@ -28,6 +28,6 @@ public void setBuffer(StringBuilder buffer) {
     }
 
     public void deParse(ShowStatement show) {
-        buffer.append("SHOW COLUMNS FROM ").append(show.getTableName());
+        buffer.append("SHOW ").append(show.getName());
     }
 }

src/main/java/net/sf/jsqlparser/util/deparser/StatementDeParser.java

@@ -15,6 +15,7 @@
 import net.sf.jsqlparser.statement.DescribeStatement;
 import net.sf.jsqlparser.statement.ExplainStatement;
 import net.sf.jsqlparser.statement.SetStatement;
+import net.sf.jsqlparser.statement.ShowColumnsStatement;
 import net.sf.jsqlparser.statement.ShowStatement;
 import net.sf.jsqlparser.statement.Statement;
 import net.sf.jsqlparser.statement.StatementVisitor;
@@ -223,8 +224,8 @@ public void visit(UseStatement use) {
     }
 
     @Override
-    public void visit(ShowStatement show) {
-        new ShowStatementDeParser(buffer).deParse(show);
+    public void visit(ShowColumnsStatement show) {
+        new ShowColumnsStatementDeParser(buffer).deParse(show);
     }
 
     @Override
@@ -261,4 +262,9 @@ public void visit(ExplainStatement explain) {
         buffer.append("EXPLAIN ");
         explain.getStatement().accept(this);
     }
+
+    @Override
+    public void visit(ShowStatement show) {
+        new ShowStatementDeParser(buffer).deParse(show);
+    }
 }

src/main/jjtree/net/sf/jsqlparser/parser/JSqlParserCC.jjt

@@ -407,6 +407,8 @@ Statement SingleStatement() :
         |
         stm = Set()
         |
+        LOOKAHEAD(2) stm = ShowColumns()
+        |
         stm = Show()
         |
         stm = Use()
@@ -538,13 +540,23 @@ UseStatement Use(): {
     }
 }
 
-ShowStatement Show(): {
+ShowColumnsStatement ShowColumns(): {
     String tableName;
 }
 {
     <K_SHOW> <K_COLUMNS> <K_FROM> tableName = RelObjectNameExt()
     {
-        return new ShowStatement(tableName);
+        return new ShowColumnsStatement(tableName);
+    }
+}
+
+ShowStatement Show(): {
+    String name;
+}
+{
+    <K_SHOW> name = RelObjectNameExt()
+    {
+        return new ShowStatement(name);
     }
 }