WallFilter improve multi-tenant support

src/main/java/com/alibaba/druid/sql/visitor/SQLASTOutputVisitor.java

@@ -942,19 +942,25 @@ public class SQLASTOutputVisitor extends SQLASTVisitorAdapter {
     @Override
     public boolean visit(SQLJoinTableSource x) {
         x.getLeft().accept(this);
+        incrementIndent();
+        
         if (x.getJoinType() == JoinType.COMMA) {
             print(",");
         } else {
-            print(" ");
+            println();
             print(JoinType.toString(x.getJoinType()));
         }
         print(" ");
         x.getRight().accept(this);
 
         if (x.getCondition() != null) {
+            incrementIndent();
             print(" ON ");
             x.getCondition().accept(this);
+            decrementIndent();
         }
+        
+        decrementIndent();
 
         return false;
     }

src/main/java/com/alibaba/druid/wall/WallVisitor.java

@@ -28,6 +28,8 @@ public interface WallVisitor extends SQLASTVisitor {
 
     List<Violation> getViolations();
     
+    void addViolation(Violation violation);
+    
     boolean isPermitTable(String name);
 
     String toSQL(SQLObject obj);

src/main/java/com/alibaba/druid/wall/spi/MySqlWallVisitor.java

@@ -71,6 +71,10 @@ public class MySqlWallVisitor extends MySqlASTVisitorAdapter implements WallVisi
     public WallConfig getConfig() {
         return config;
     }
+    
+    public void addViolation(Violation violation) {
+        this.violations.add(violation);
+    }
 
     public List<Violation> getViolations() {
         return violations;

src/main/java/com/alibaba/druid/wall/spi/OracleWallVisitor.java

@@ -71,6 +71,10 @@ public class OracleWallVisitor extends OracleASTVisitorAdapter implements WallVi
         return config;
     }
 
+    public void addViolation(Violation violation) {
+        this.violations.add(violation);
+    }
+    
     public List<Violation> getViolations() {
         return violations;
     }

src/main/java/com/alibaba/druid/wall/spi/SQLServerWallVisitor.java

@@ -68,6 +68,10 @@ public class SQLServerWallVisitor extends SQLServerASTVisitorAdapter implements
         return this.config;
     }
 
+    public void addViolation(Violation violation) {
+        this.violations.add(violation);
+    }
+    
     @Override
     public List<Violation> getViolations() {
         return violations;